I think the gun, like four or five I have seen before, is a gun rebarreled by Francotte. Had a nice SLE at one time, with no name on the receiver, but Francotte on the barrels. The serial number of that very high quality SLE did not fit at all into the known Francotte range. It's a good enough gun that it would have been worth rebarreling.

http://www.bakercollectors.com/