Looking at this topic, I would like to add that an Italian firm "Antonio Zoli" made a similar rifle in the early 1980's in percussion.
They made it for a short time as I would suspect there was no a lot of interest, as it was not a "Hawken" which was the rage of the time.
Watching the video and seeing the fine rifle, I was surprised to see the similarity.
The Zoli went so far as to include set triggers, color case hardened nose cap, butt plate, and patch box.
The stock is walnut (American?) and fine checkering on wrist and forearm.
Caliber is .50, and sports a buckhorn rear sight, and a low and small front sight.
I have had it for several years, 10+ and never got around to shoot it.
If I could post pictures, I would, but I am too much of a knuckle head to do so.
Thank you for posting the information and video.