There's a builder by the name of John McGuire in Tennessee who builds them and is considered to be "the guy" for it. Mine was built by him...but bought 2nd party locally.
You send him the parts kit and he has it assembled, parked, test fired and on its way back to you in 3 days.
You send him the parts kit and he has it assembled, parked, test fired and on its way back to you in 3 days.