Sir nice job for the time, back then not many people know about SB guns, in the 197s the person that did was Leonard Day, he passed away FEW YEARS AGO SADLY.
His son JOHNATHAN DAY is doing some work on bringing back his fathers guns, look him up for help or to maybe to fix this old rifle. I sell parts to build SB actions, and have a few sets left, give me a call to see how I can help. Bernie at pioneerarms.com