New to me 1921 Luger

[redgun]

I have an opportunity to aquire this 9mm luger from a friend. It is a DWM with a stamp on top of the receiver of 1921. It appears to me to be all original with matching numbers except for the plastic bottom magazine whis is not numbered. I do not know the story or what the stamps and proofs mean , so am looking for any information you guy would be willing to provide. Estimated value range would be great if possible. Thanks for your help..