So, as per requested more pictures of the action. There are a few chips in the wood work. I wouldn't try to fire it (even if I were into black powder), but both hammers seem to work - they pull back, lock, and go when you pull the triggers. The barrels do seem thin, and as far as I can tell via flashlight there's no rifling.
The inscription seems to say "CANON CAIN" but I"m only 100% on the "Canon --in". The gold leaf is pretty worn, and the writings so stylistic it's hard to figure out partial letters. Sorry about the quality of the pics - my camera probably has a setting that would have made everything show up, but I haven't found it yet.
Whatever it is, someone spent a lot of time making it.
I ran a hoppes gun cloth over it to get rid of some of the dust, but I don't want to scrub.
One issue I have is - if it is valuable/historical - the humidity around here will ruin it - I live on the edge of a swamp. Duracoat isn't really an option on this one. Any suggestions for keeping it dry?