Hungry Horse, I believe that you are correct, an "update kit" was marketed for the Sharon locks but I don't remember if it was for Long locks or not...it seems like it was for L & R? I have had occasion to "rebuild" a Sharon kit Hawken. I bought one poorly assembled at a gun show in the early 90's for $60. The entry pipe along with the stock went in the trash and I restocked it with the other original furniture. It was a great shooter and I wish I still had it..
Bob has a good point. just because a part is from a well known old builder does not make it good. You really have to be careful about what you buy when you buy old parts. I always search for Large, Sharon, Green River, and H & H barrels, ( there are some other good barrels also), but my preference in locks is limited to Roller, Schillinger, Robbins and maybe a real clean Cherry Corners. Other than these I would really be careful.
Just my 2 cents....