Welcome to Vermont, Wayne.
Full auto, select fire, and supressors are about the only things that are not legal here. The Uzi and the AK pistol are used surplus items that probably go through a reconditioning at Century Arms in Georgia Vermont before being distributed to dealers. The MAC10 is made by Masterpiece Arms. https://www.masterpiecearms.com/proddetail.php?prod=MPA930T&cat=27
You could probably order one in NY, although I’m not sure what your restrictions are on magazine capacity and threaded barrels. Which makes no sense here because you can have a threaded barrel but no supressor, but a fake supressor is fine lol.