Is this really a rifle?
I see no rear sight and a metal ramrod is more common on shotguns.
The (Star) N and the Peron you show as --> are Belgian proofmarks.
Edouard de Beaumont was a noted Dutch gunmaker in Maastricht, Holland, better known for the Beaumont service rifle. I found mention of him either using Belgian made shotgun barrels or selling Belgian made shotguns.
Roermond is in Holland 49 kilometers from Maastricht. Maybe he had a retail store there, but I cannot find mention of it.
I think the hammer is a replacement, the screw is not through the "fat" part of the hammer, but placed where it had to be to hit the percussion cap.