I do not know what that is, and not likely terribly helpful with the following. I think the word "musket" used to refer to a thing with a smooth bore - so a "rifled musket" must have been from transition thinking? I believe most all were originally made as muzzle loaders - pour powder, wadding and bullet(s) into muzzle end - then, I believe many countries had the rear of the barrel machined open and a latch affair installed - allowed a breech loaded cartridge to be inserted into rear end of barrel. I think most re-used the lock mechanism, etc.
So to ID that, likely need to take a look into the bore - does it have rifling or not. Then look around that hammer - has the rear of barrel been machined and replaced with an opening latch of some type? And the hammer - what, exactly, does it strike upon, when the trigger is pulled. I am sure there will be some on CGN that can ID it simply by a close, clear view of the hammer and lock area - also any stampings that might still survive.