Yes aware of backwards site that's been remedied. Older pic. I do think it was added later. Best match I can find is the tc tang. My uncle was kind if an accuracy nut. He may have added it sometime. He owned a shop in Millville, PA. Ball-Accuracy. The two guns I have that he built, a half stock Hawken and a Pennsylvania long rifle are tack drivers. They are .40 and .45 cal respectively. I have killed deer with both. As of about 4 yrs ago the Brockway shot nice as well.