You got it.
Combination of Yank type naked barrel and Euro hogsback stock, it could be as you said, an American barrelled action in a Lux stock either as a swapout or special order.
Differences you may have noticed are a stirrup sling loop instead of the usual Uncle Mikes stud and swivel. I think it has a better finish than current rifles, too, even though it has had a lot of use and maybe some knocking around from all the dings in the bolt handle.