I am presuming that you wanted 24x36mm picture in a larger black frame, otherwise Rick's suggestion makes good sense. In the U.K. several years ago you could get key holders with transparent fobs( do they use the same word in the U.S.?) that could be opened and a small contact print could be inserted. I have often thought that a 35mm contact print might be ideal for such key fobs. It just about big enought for some kind of shots

Just as an interesting story that is related to your thread. In the 1970s you used to get photographers who'd take a photo of you and your wife/girlfriend on 110 film when you entered a nightclub and then offer you a small key fob with I think a transparency at the end of the evening. The fob would have a small magnifier built into the plastic so the romantic shot would look a reasonable size. A memento of the evening.

You could always tell the guys who were there with the wrong "wife or girlfriend". They always refuse the offer to buy on the grounds that the picture didn't do him and his partner justice. No evidence, no crime :