Larry, of course the terminology can be misleading. The French marked, Belgian proofed guns , often seem to have a French flavor to the finish and engraving. Surely some were "finished up" in France much like Birmingham guns were "finished up" in London. a
As to Gastinne Renette, I know they were a huge store, selling much more than firearms, but for the most part their doubles were beautifully refined, with engraving unlike guns with Belgian names on them. Of course there were barrel makers like Bernard etc,--do you know where they got their tubes ? I have also owned a Cogswell and Harrison , Paris address, with Austrian proofs. C and H have no record of this exact gun, but one can only wonder about it's history. I don't know the French proof laws and wonder if they accepted Belgian proofs in France.