Very nice. As you have noticed, the brass mounts denote that it is the naval issue, also used in French colonial service. Too bad the original stock has been cut back, that is a rare one. What is the barrel length? Interestingly enough, the Commonwealth of Virginia purchased a number of these brass mounted M1777 muskets shortly after the Revolution for the state militia, one still exists with markings to Rockbridge County. Do you have any history of the gun? Is there any evidence of markings on the top of the barrel other than proofmarks?