If the head of the stock is sound, another option to get your desired length of pull, and other dimensions as well, would be the butt transplant as described in Shotgun Technicana. It has been discussed here at various times. Depending upon the overall condition and value of the gun, it might be better and cheaper to pass on this one and let it find an owner who is happy with 14" LOP. I'm not sure you'll find original 15 1/4" length of pull without adding a pad though.

Voting for anti-gun Democrats is dumber than giving treats to a dog that shits on a Persian Rug