Jeff this really belongs in the buy and sell column. An S.G. stock with a stamp of RSG and a number is normal. Made by Robert Irwin for not only S.G. but also for S'G'. So they made stocks for both plants of Saginaw Gear. S'G' stocks will not have a number. Now you need to know which type stock you need. All three types had the S.G. with a crossed cannon stamped in a box.