Just so you know and are not disappointed, there is no mention of “canoe” guns in the historic record.
The guns used by the Voyageur prior to the F&I war were factory issued, typically what we now refer to a type C and type D French fusils. They had barrel lengths of 36 to 42 + inches.
In the late 18th and 19th century the canoe guns issue to the Voyageur brigades by the Hudson’s Bay Company and their competitors the Northwest Company, which we now referred to as “North West” guns were also of the standard 36 to 42 inch length.
Now all this does not mean that an individual did not cut down their barrel length. Indeed there are many examples of shortened barreled guns in use by Native Americans and others for buffalo hunting and horseback use. 18 to 20 inches seems to be a popular length for these shortened barrels.
However, the “sawed off” shotgun or “canoe” gun was not a factory option in the historic record. The only documentation I could find for a shortened barreled factory order was in the cartridge era, when Well Fargo requested the Ithaca Gun Company shorten their double barreled shotguns from 36” to 32” for use on their stagecoaches.
So in case anyone should ask you about your Canoe gun, you know that the shortened barreled guns that appear in the historic record are done at the request of the owners rather than issued by the gun making factories.
I know some folks who are sticklers on such points; personally I had a friend with a 28” barreled smoothies that I thought was the perfect length for a hunting gun.