One of my buddies bought a mak90 at the recent gun show with a side folding style stock. Thinking that the person that he bought it from knew the gun laws he did not deam it important to check and make sure that the stock was welded or pinned open. After discovering that the stock folded he opened the dust cover and discovered that there were no modifications to the rear trunion, it had not been replaced. Would this mean that this was the original trunion and stock? The stock doesnt have the push button folding operation, it has a paddle that you depress(much like on a magazine release) It also has an intact threaded barrel that wasnt welded, with slant muzzle break. The rifle is completely matching serial numbers, stamped mak-90, and in excellent shape. There is no place to put a cleaning rod on the rifle either. What does he have? Also what kind of stock is that?