The Silver Legion of America, commonly known as the Silver Shirts, was an underground American fascist organization founded by William Dudley Pelley that was headquartered in Asheville, North Carolina and announced publicly on January 31, 1933. The group was effectively dissolved on December 8, 1941, when police called for the open arrest of any individuals associated with the group.

Wikipedia says your larp is 80 years out of date, but okay.