I believe things are easier in that special case.

A closer look to the details of the additional mount show the typical work of the 1950/1960 period.

The socket soldered on , the thinner and slighly longer base for the claws. And certainly the surface treatment of that base will differ from that one slotted into the receiver ring(the original base!)

There is no logical reason that somebody had mounted a Zeiss Zielvier and a Zeiss Zielsechs in the days when the rifle was assembled.

BTW : The price for one scope equalled the price of the rifle.

Do what the preowner did.

Choose a more modern scope (post WWII) and let it mount by a competent and knowledgeable smith.

That will not sacrifice the originality of the rifle(at least no more than still was done ).