All good guesses, but one thing for sure is that it was made for export since it is stamped in English. I'd say "Century" is the best guess, since it also has an Oppenheimer/Chacom connection, if tenuous. La Bruyere, with whom the French Comoy merged to form Chacom, used the term, as did GBD. Still, only a guess.
Looking at the profile image of the pipe I can see the gap between the stem and shank that you're asking about and no, it's not typical. In the image the connection looks slightly off kilter. The Fleur-de-lis on the stem suggests that it belongs to the pipe, but to my eye it just doesn't go with it. Too big and wide where it meets the shank for such a graceful piece of carving.