I believe that it is a fake for the following reasons:
- If it had been marked in France, it would have shown "Canons" because there are two on that gun.
- "The proof marks" are unknown to me and my books. They vaguely resemble the old St Etienne Palms.

As a note, I believe that Faure Lepage in Paris has nothing to do with Lepage in Liege, at least in the late 19th and 20th centuries.
Best regards,
WC-