I may have a chance to acquire a Spanish M93 carbine in payment for rebluing several rifles. The M93 lacks a bolt sleeve shroud and lock in it's design. Can either be installed? The rifle has been truly bubba sporterized so it's lost any collectible value but it would make a really nice featherweight hunting rifle. It looks to be a 1916 rifle and probably has adequate strength steel but I would just stick with the original 7 mm unless the barrel is shot. If it is I wonder if a surplus Swede 6.5mm would easily fit the small ring receiver?