Hi Bob,

I doubt you're going to have any problems. Legally, there is really no one alive to claim an infringement unless the next of kin decides to claim it as inherited intellectual property. And personally, if my family were the type to do that, I don't think I'd care much about preserving the history of them. YMMV.

Seriously, with no copyright markings, you shouldn't have any problems with it. If the copyshop says they can't do it, tell them it's your product.