I know this "club" was CMP-affiliated when I first "joined" 10 years ago but I never saw a way to get a membership card or other documentation that CMP wants to verify your membership (not that it mattered as my then-active duty military ID and membership in the Garand Collectors Association sufficed). Members here should be aware that active duty or retired members of the military qualify for the CMP simply by sending a scan or photocopy of their IDs in. Of course, there's that whole "do not copy your ID" instruction but I doubt the CMP is going to use their membership files to falsify ID cards.