What I see is a very nice double, proved as the 4310th gun in 1931 in Ferlach, and most probably made there. I don't see any connection with Pegam of Ferlach, nor do I see any other individual maker's mark.
What is the connection with Arnošt Adler of Pribram? Is he marked on the rib? If so, he was clearly a retailer. Ferlach guns were popular in Czechoslovakia.
With kind regards,
Jani