yes, this 19,69 cm is a lot I have to measure 6x scopes to see if this was possible or we had the next bigger class - Zielacht. What ever it was a 8x scope allways looking like a stove pipe. the 6x scopes are more elegant and like I say before welding change in any direction. you have a great selection of second hand scopes on the market from the 1960s and 70s that coming in excellent quality.

soft soldered scope rings are better but I was making it simple for you! this is a LOT of work.
you have to find a steel tube scope in this size thats in good shape. probably such an old scope have to go for an overhaul to a scope specialist before and thats not for nothing.the scope have to be dismantle, the scope is soldered to the rings, the scope is put together and you test the rifle. if you hit the paper you do the next step if not do it again. if it shoots you dismantele the scope again and rust blue everything, then assemble it again.
windage correction for old scopes is made by a more complicated forefeet.
with a more modern scope you have a screw on the right side and dont need it.
I can understand what you mean because I collect bolt action hunting rifles and whenever there is a gun that lost the scope I try to give it a period one.
whats ok for me is maybe a bad advise for you.