Whew! Better late than never, I guess!
I'm thinking that if it's a small enough shop, the Maurers/C3, etc. wouldn't be bothered. I'm showing my age here, but I remember that there had to be thousands upon thousands of fake Michael Jackson products being sold around '83. Around the same time, I recall seeing plenty of bootleg Cabbage Patch Kids, usually called Cotton Patch Kids or something like that. I suppose you could just ASK them (with a little force, of course) to stop selling the products, but they may not even want to be bothered.