My first guess is to fit new pins to the action. Second,rework the link. Third and hardest, move barrel back a few thousands-there were other fixes;like a spring bearing on the lever(front part) . I would try the larger or new screws first. Your malady is kind of common on this model. Lets be generous, its over 50yrs old. If the chamber is good,AND the extractor is in good shape and not wallowed out(good KY language),aprroach this fix slowly. JMHO Paul W