I incorrectly stated in my original post that my Perka camera was double extension; it is in fact a triple extension. I was able to get a little more information from European collectors. It is a Perka Model 1 but it does appear that Perka cameras are something of a mystery both in terms of when they started trading and when the company actually stopped. I do have a name of one of the directors though. Herr Heinrich Gerl was no longer managing director from the beginning of 1930 (Die Photographische Industrie 15. Jan. 1930 p60). However I have no information as to whether his departure signified the end of trading or just the end of his involvement. I have been able to find nothing else about this gentleman despite extensive internet searches. However a another 'Gerl' does pop up quite frequently as a graphic designer also based in Munich. Possibly a descendant or maybe just a common name.
I was able to find a bit of contemporary adverting but it is very poorly defined and difficult to read. I have as yet not been able to translate this. See Pic.