There is a signed Martin Boyer swivel-breech double rifle. Only signed gun of that era I have ever heard of. As you may know there was an early article in PA Gazette that there had been a fire and explosion in Haga's gunshop. I believe he was injured and that thereafter he supervised some gunsmiths, journeymen, apprentices. I also strongly suspect Boyer was among his apprentices. Kindig had a whole wall full of "Haga" guns, all in excellent condition. Strange this is that altho I have photo'd easily25 Haga guns I never saw one that was damaged, rebreeched, etc.