Roy Keeler was a fairly prolific lock maker in the 1950s and 60s. He made workable flint locks and was a solid guy to do business with. That is a nice Bedford style percussion lock. I do not know enough about Roy's rifle work to speak to this rifle being his work or not.
Many of these "mid-century modern" muzzleloaders do not get the respect they deserve. They marked a major resurgence in interest in muzzleloaders and most were serious range or hunting guns. Made to use, not hang on the wall, they reflect some of the limited knowledge on styles and schools we have developed today