I am helping a friend out trying to get info on a gun. It has been in a safety deposit box for 35 years. It looks to be a colt walker, fo not know if original or replica. Any way it has this what looks like a copper bar screwed on to the bottom of the butt that is ingraved SGT COOK. Everywhere else it says A Company No 48. Do any of you know where I can research to get more information??? Thank you so much!!! I can picture if any one is interested.