Rigger, if you strike out here (which I seriously doubt--keep checking) try "The Italian Gun" forum over on http://www.gunboards.com also. You might strike lucky over there. Pictures of the proof marks and the gun itself would also help, on both forums. Failing that, a complete description of markings on the gun and their locations would also be helpful. Barrel steel marking is almost certainly "Boehler," a common and excellent German-supplied steel ("Boehler Blitz" = Boehler Lightning).