MGC THOMPSON 1921 HISTORY/AMMO/VALUE

I HAVE A MGC MODELGUN CORP 1921 THOMPSON . FULL AUTO, BLANK FIRING GUN. DOES ANYONE KNOW ITS VALUE AND HISTORY. WHAT SORT OF LOADS DO YOU USE IN IT. IT HAS AN OLD US SURPLUS 30 RD STICK MAG THAT CAME WITH IT. IT IS IN APPRX 98% COND WITH ONLY A FEW SMALL MARKS IN THE PARKERIZED FINISH. I WOULD BE THANKFUL FOR ANY HELP YOU COULD GIVE ME WITH THIS.

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