Thanks for your post but all three chips that we could identify are listed in the Chip Guide. David Spragg remembers someone trying to sell them years ago. And, some of the Shamrock Chips were highly sought.

http://chipguide.themogh.org/cg_chip2.php?id=MTMCMC&sort=type

And, the Shamrock Club listings:

http://chipguide.themogh.org/cg_chip2.php?id=NVCASC&sort=type