Help identifying 19th century smoothbore

[xlch58]

I bought this double barrel original smooth bore at a local gun show. It had a host of ills, but now it is just missing a hammer and I need to machine a new tumbler for it. The hammer is a basic forge a file job. The bore is also rough. It is close to a 24 gauge, but the barrels are very heavy. I suspect it might have been a double rifle at some point. I plan to make some reamers and clean and hone the barrels up. I work on a lot of originals, but this one has no makers marks on it at all. It feels Belgian to me, but I am a smith, not a historian or collector, so I don't know. Any ideas?

https://ibb.co/ceewbG
https://ibb.co/na6yqb
https://ibb.co/dAYpwG
https://ibb.co/hnShGG

Charles

 

[Wes/Tex]

That's certainly different alright! Don't recall ever seeing one quite like it. Since I don't see any trace of sights, I'd say it was a shotgun. Look under the barrel breech as well, sometimes proofs and
codes are stamped there!

 

[Story]

Disassemble it yet? Proofs on the undersides of the barrels might yield some clues.

 

[xlch58]

The only marks on the barrel are on the barrel next to the breech plug where you would expect the proof marks. The left barrel has the letter P stamped on the bottom, the right barrel has the letter O stamped on the top.
I did notice today when looking at the barrels again that next to the stamped letter P looks to be engraved "S W"/ The barrels attach to the cast iron wrist via a clamp that grips the dovetails on the barrel plugs. Looks a lot like percussion over and under guns I have seen. The lock plates are cast and fit tightly into the wrist casting. The metal was once well finished.

Charles

 

[Feltwad]

I would say it is not Belgian if so it would have had the Leige proof marks ,could it have been built out different gun parts ?
Feltwad