USMC 50 Cal Bottle opener help!

I need some help, I am looking for a 50 cal bottle opener for my father in law.  I have the NRA version, once he saw this he flipped! 

Any help is appreciated, he is a USMC Vietnam veteran (helicopter gunner who shot a 50) and I would like to hook him up with a kick ass birthday present. 

Does anyone know where to find one of these??


Thanks for the help in advance!