gunmaker,
Is your rifle equiped with old scope bases? If it is still untouched, and "collectors grade", I would think twice before blessing it with a scope. I once did that to a 1935 Merkel DR, but it is still my most used rifle and the mounts I decided upon are the correct (if somewhat expensive) claw mounts. The scope is not vintage but rather Leupold 1.5-5X.
With this exception, all my old rifles that I put scopes on, already carried (empty) claw mount bases. I mostly used Nickel Marburg scopes from around 1970 as a compromise between vintage and modern.
If a prewar 4X scope is prefered, I would probably decide on Zeiss Ziel4 which was already mounted on some of my prewar rifles and drillings when I got them and seems to be of excellent quality.

Cheers,
Jani