1921 DWM just acquired

[JBBOOKS]

Good Day All,
Just got a call from a friend who owns a local firearms shop. He deals mostly in hunting and archery but knows I like "old" guns. So here it is. Is this a Police issue? There are no unit or import marks. All parts match and the grips do not have the "million dollar chip". What can you tell me about the "ers." stamp on the second magazine, is it a Police unit mark? The holster is in good condition but the take down tool is missing. The story with the gun is that it is a WWII bring back but it does not have any paperwork to prove it. The pistol, two matching magazines, and a nice holster for $900. What do you guys and girls think?