There was a smith up in Montana , cant remember his name off the top of my head , but I have contact info around here somewhere . He sold a kit which consisted of an action and barrel . No tank and no loading tube . The action was also a modern set up so while things looked right on the outside , the workings were different .
He at the time offered 3 different early air rifle action designs , Jover ,Evans and the Girandoni.
Prices as I recall, ranged from 500.00 to 1500 . But that was several years ago .
I talked with him a couple times concerning a Jover action . I do remember him telling me he wasn’t going to continue carrying the early styled actions as there had been no real interests . He however had a lot of work building magnum air actions for modern air rifles in centerfire calibers .