IBM AO mutt

I have had this one for a couple of years and finally decided to take it apart. I think it might have been through Israel. It also has the Birmingham Nitro Proofs, crossed swords F 3 D. It has a small aluminum rack tag fixed to the right side butt stock # 1348. The Barrel is 44 dated Underwood, receiver is IBM sn#3846468 and AO. Bolt is flat top marked .U. Op slide is (.U.). Trigger assembly is laminated sheet metal marked .U. Walnut stock and hand guard is OI with faint AAA stamp. Rear sight is milled adjustable PI. Upgraded flip safety and MAD mag catch. EMQ marked bayo lug/ swivel. The metal is a consistent dark oil stained park finish. The rifle looks like it has been handled alot but the bore and internals are in very good condition. No import stamps...I looked for the small SACCA one along the receiver.