I've took a look at that catalogue from 1931. Found parts of the things here too:
https://www.pacificrimcamera.com/rl/00442/00442.pdf
But what is that adapter from page 11? It's a kind of back like the one used in some medium format S.L.R.'s?
In the 1931 catalogue they are mentioning that some cameras could have attached tele-lenses. Those lenses screw over the existing leneses?
"Voigtländer" Berghiel is intresting... but I doubt that I will find any in Romania.
As I sayed before, I'm instrested in a camera like this only for taking views of the city. For fast action I will use S.L.R.'s or digital stuff. I want medium format for some stuff because it does offer more details. Of course it can be done with digital, but a good digital camera I don't think is so cheap. And digital cameras are heavy. A metal body "Zorki" or "Minolta" is light compared to them.
But what in the world was the "Zeiss-Ikon" Mirax?
As for lightmters, the famous company "Gossen" made some that could be adapted for different agnles. The 'Luna...' series. Found them in Romania, but at high prieces and no adapters. For the moment I do have a 'Sixomat' (Selenium lens) which I think works pretty fine, except for the time when light is powerful (gives one step overxpousere). I made a compare with the lightmeter from my "Minolta" X-700 camera.