Yes it is a French M1786. Gilierson's "BOARDERS AWAY II" has info on it, last I checked the entire book was online via "Cheaper than Dirt." Hard to say what one in that condition would bring, best I could advise is to look for something in mid-4 figs somewhere. The French must have cast thousands of those; I've seen probably 50 just in the US, no telling what the total number of survivors is.