You need to seek a professional appraisal
350 - 550 depending of condition and completness of box, manual etc.
No published sn data for Interarms PPK
I recently saw a used Interarms model in averaqe condition for $420, no case or manual included.
See Dieter Marschall's book Walther P1-99
no published sn data.
100-1000 depending on the usuals.
100-1000 depending on specifics
100-1000 depending on specifics
100-1000 depending on specifics
There were two companies known as Interarms. The first was an importer/exporter, formed in 1953. They did not manufacture firearms. The second - and current - Interarms is a subsidiary of Hi Standard, and does not manufacture a PPK or PPK/S pistol. If what you have is actually a Walther PPK/S, value could range anywhere from $300 - $800, depending on specifics.
Need a detailed description of ALL markings.
100-400 USD