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Sounds tropable.
There's a Peanuts strip
where Lucy destroys Schroeder's Beethoven bust to get his attention. Schroeder calmly goes over to the closet to get another one (we see six spares).
The joke where a character always wears the same outfit, but it is revealed to be just a bunch of identical outfits for comedic effect
Limited Wardrobe already covers this. In fact, the page image is exactly what you described (discounting the single grey shirt).
"I've also seen it used for things other than clothes"
A joke where a character opens a closet/wardrobe/drawer/etc. and reveals rows upon rows of identical copies of an item we've already seen and assumed to be unique. In its most common form, this is used as a form of Lampshade Hanging of a character's Limited Wardrobe, but I've also seen it used for things other than clothes e.g. in this scene of Spongebob: https://www.youtube.com/watch?v=NCOaX_tV4dw