She's been through some different services: Imperial German Army, Weimar Reichswehr (that's the 1920 marking over
1917), very likely used in WWII and captured by Tovarich, later re-worked and re-issued to the East German Volkspolizei
(People's Police), a so-called VoPo-Luger.
The grip panels and script of the mag serials are a dead giveaway for the latter; also the newer barrel. These pistols were
re-worked and most of them re-barreled in Suhl. The "crown/N" is the Suhl proof mark. There should also be a "sunburst"
mark present, indicating VoPo service.