McCoy from the Area 88 manga and anime combines this with Honest John's Dealership. He is especially good at acquiring hard-to-find aircraft and claims to be able to deliver the Kremlin if given enough cash, and at the height of the Cold War, no less.
Doraemon has a fourth-dimensional pocket full of stuff—but because he's horribly disorganized, he occasionally can't find what he wants and he owns a frightening amount of useless gadgets.
In IDW's G.I. Joe series, the G.I. Joe program has its budget severely cut and Hawk is removed from being its commanding officer. Hawk tells his replacement Duke that, with its reduced circumstances, what the Joes need is a good scrounger. As one of his last acts, he recruits Billdocker (an Air Force master sergeant) to fill that role.
Bill Mauldin's Willie and Joe are this to an extent. They are shown loaded down with extra equipment, to the point where one tells the other, "You're tired 'cause you carry too much stuff. Throw the joker outta your pack of cards."
Lt. Kirce James in the Tiberium Wars fanfic is described as self-important and irritating but her commander still has a grudging respect for her because she was able to scrounge up high-tech equipment, Kill Sat support, troops and Mammoth Tanks on vital moments.
Célestin Poux in A Very Long Engagement, famed throughout the rank and file for pulling various tricks in order to keep the troops supplied with food.
Kris Kringle in Miracle on 34th Street is this. He apparently knows where to purchase anything - even specific and expensive medical equipment.
The droid Emtrey in the X-Wing Series had a special personality program that he reverted to when told to "scrounge up something." It was something to behold.
Though they rarely relied on this trope, Wraith Squadron officially split "field requisitions" between its real quartermaster and ex-thief Falynn Sandskimmer. They weren't much for scavenging, overall, preferring the simplicity of stealing enemy materiel (sometimes while the enemy was still using it).
Gunner Jurgen from the Ciaphas Cain stories might fit. He's shown a great deal of skill at finding or 'acquiring' things that Cain needs, even before he knows he needs them.
Obergefreiter Joseph Porta, from the novels by Sven Hassel.
Pete "Dracula" Szábo from the Worldwar series is described as "the best scrounger I've seen, and I saw some real pros during WWI", by his field-promoted lieutenant. Said Lt. often benefits from this, since "keeping the Lt. happy is a legitimate business expense for a scrounger".
Milo from Catch-22. No matter what you want, he will get it for you, as long as you pay the price.
Nobby Nobbs from Discworld is a petty thief and police officer who is known as the person to ask when you need anything important or if its missing. If he wasn't the one to steal it, he knows and/or is usually related to the person who did.
Also one of the many high-quality services provided by Igors. After all, the Mad Scientist can't be running around all the time looking for copper tubing, turnips, and useable corpses. Of course, they do all of their best "shopping" at night, in the rain.
Stanislaus "Kat" Katczinsky from All Quiet on the Western Front, whose ability to find decent food and shelter is treated as something of a sixth sense. Notably, it's a sign of how bad things have gotten when he can't rustle up anything.
The Finn from Neuromancer, and William Gibson's other stories, is pretty much defined by this trope. He is never even seen leaving his apartment, but somehow has it crammed to the ceiling with useful computer parts and cyber technology and useful information to sell the various antiheroes in the Sprawl world. When asked where he got a piece of equipment or how he learned a valuable piece of information, his reply (at least twice) is, "You know how many times I've been asked that? You know how many times I'd be dead if I answered?"
In John Hemry's Paul Sinclair novel A Just Determination, at the trial, Sup is asked whether he is strict about regulations, and explains that he is a good supply officer. One of the members interjects to explain that everyone knows that good supply officers get what is needed rather than worry strictly about regulations.
Live Action TV
The genius engineer Seamus Zelazny Harper from Andromeda is both a Mr. Fixit and The Scrounger, as he grew up on Earth, a hellhole of a planet where the remaining population was enslaved by the genetically-enhanced Nietzscheans and preyed on by raiding troups of the man-eating Magog. Consequently, Harper grew up as a thief, loyal only to people who treat him well, trying to survive at all costs and willing to swindle and steal equipment at gun-point if the crew needs it.
Unless what's needed is a weapon. For those, ask Fiona.
Barry the Money Launderer on the same show.
The mother occasionally finds stuff too, mostly old memories related, sometimes other things. Micheal Weston isnt too bad at finding stuff either.
To some extent, Private Walker from Dad's Army. He's able to get supplies and occasional off-the-ration meat on the black market. Captain Mainwaring usually turns a blind eye to the illegality because Walker's acquisitions are so useful to the Home Guard regiment.
Corporal Walter Eugene 'Radar' O'Reilly from M*A*S*H was definitely The Scrounger, and a Knowledge Broker in that he seemed to know everyone important in the Army (supply officers and secretaries, that is, people who actually did stuff and could lay their hands on stuff, instead of the high military brass). Radar is not a Mr. Fixit, however.
His successor, Sergeant Maxwell Q. Klinger was able to wheel and deal with the best of them, explicitly calling himself a "scrounge".
Between them, if you gave them enough time and resources Garak and Quark could probably come up with anything you need on Star Trek: Deep Space Nine.
Nog too. Lampshaded in "Treachery, Faith, and the Great River".
This conversation from GURPSTraveller 3e Ground Forces is too funny not to share.
Lt. Dylan: Explain it to me again, Sergeant, and do it slowly.
Sgt. Dollar: Certainly, sir. We are 450 units short on Mk52 Medikits, Individual, but the 6,943rd Separate Evac has that many, so I'm going to make a trade with the 2nd Highpoint Lancers.
Lt. Dylan: Call me slow, Sergeant, but why are you trading with the Lancers if the medicos have what we need?
Sgt. Dollar: That's simple, sir; they don't want the M-348A2 stabilizers, but they do want several bottles of Glisten vodka and some real limes. The Lancers just got several cases.
Lt. Dylan: (starting to visibly lose it) And why do we, an [infantry] unit, have stabilizers for [heavy grav tank] main guns?
Sgt. Dollar: (shamelessly) Beats me, sir. They were already buried under the parade ground when we got here.
Weird Wars setting for Savage Worlds has this exact Edge available, complete with the system as to what and how much exactly a Scrounger can appropriate per session. Correctly identifying Scroungers of neighbor friendly squads and keeping them away from your position is a subgame.
In Shadowrun, the Jackpointer known as Mika was this during his conscription. It should be pointed out that his skill as a scrounger got him his nickname, which means "Intelligent Raccoon" in Lakota.
A few character types in Dungeons & Dragons can do this. For instance, as a class feature, a Menacing Brute can try to find a nonmagical, non-masterwork piece of equipment in this manner once per day, with more expensive items requiring more time, a larger community, and a more difficult skill check.
In 1943, OSS agent John Caskey arrived in Turkey with $5000 to finance the supply of Greek partisans. Upon asking the US Ambassador how to convert this into gold he was told to go see Earle Taylor who went into the bazaar and somehow came up with the coins even though it was a weekend and the moneychangers were all resting. Somehow the gold was obtained (for a twenty-percent fee as Earle apparently believed in making patriotism pay ). No one was quite sure how he got the gold that quickly.
In the restaurant business, these guys are sometimes known as débrouillardsnote French for "unscramblers", though a more appropriate translation would be "unconventional problem-solvers", and their often-sketchy methods of getting you out of the weeds by any means necessary is called Système D. Tony Bourdain has written fondly of such people (including Steven Temple, his ethically challenged but ruthlessly effective sous-chef when he was writing Kitchen Confidential). It's frequently best not to ask how they managed to get that case of tomatoes at 11pm though.