I have seen pictures of some very high grade Galands. The only one I have seen in person is a single barrel 10 gauge I own. I am guessing the date at early 1870's based on a same period W&C Scott single 8 gauge I own. It is marked simply Galand - Paris.
Odd gun in that it is much heavier and longer barreled than the 8 gauge Scott, but only short chambered 10 gauge. It is configured like a market gun but not likely capable of large kills per shot, very different from the Scott which is definitely a pass shooting gun but made with no choke and shoots bore sized balls well. Workmanship and quality are very good. Barrel is an odd amalgam of octagon rear and round front with two different composites used. It includes a rear fixed sighting device and is a rotary underlever action. It is an interesting gun.