Looking for 4-8 altered check (proxy) cards for my delver decks. I've seen some cool things folks have done with their check cards and I'd love to try and acquire some.

Have you thought about printing images you like on adhesive plastic and sticking them over the check cards?

My concern is with them being thin enough to still be tournament legal. I know there are some specific services that specialize in that sort of thing too. Open to all suggestions though!!

If they're in a sleeve and you use thin plastic or paper i doubt you'd have an issue.