NYT Connections Blue Group Hint

There’s your visual hint for today’s blue group. It might be your eureka! moment. (No, sorry, that was not a clue.) Or it might not have helped at all. Hey, we try.
Time for the verbal clue: These are things you’ll find on eBay, or at conventions, or as you rummage through garage sales hoping to strike gold.
No? We were stuck on three words for this one for a long time. Those pesky multiple-meaning words can be a pain…
Today’s blue group answer is Classic Collection Items and its words are COIN, COMIC, RECORD, and STAMP.