You have to remember that if he was militia, it could have been a variety of different arms. If he was French and in Canada - furnishing his own arm, it could very well have been a French "fusil de chase" - (trade gun). Many of the guns utilized by the militia - American militia - dated back to the F & I War as well. There were a wide variety of "Committee of Safety" long arms - some styled after military and some quasi-military. Many "militia" members, made up of locals, were required to own a firearm and serve. Calibers may vary (usually smoothbore muskets) and like any individual of that time, they would have molds to fit their individual weapons. I'm talking "irregulars" - not organized military.
I have a smoothbore that is .69 that was passed down through my family - converted from flintlock in later years. The stock design is definitely "French" but it is stocked in American Maple. Full stock - barrel bands instead of pinned barrel - I have had several knowledgeable fellows inspect it in past years when I was at Friendship for the Nationals - they said that from their inspections it would be classified as a "committee of safety" musket. No markings on it at all but stock points to a French influence and they figured that it dated to the F & I War. Oral family history has it carried during the Revolutionary War - but i have no written or solid proof of that other than oral history. That part of the family came from NY state. I'm still working on the genealogy and hopefully I can establish a Rev War Veteran or F & I Veteran to whom it may have belonged.
If a pair of '51 Navies were good enough for Billy Hickok, then a single Navy on my right hip is good enough for me . . . besides . . . I'm probably only half as good as he was anyways. Hiram's Rangers Badge #63