Hi! Welcome to the forum!
Looks like a nice gun
On pages 21, 22 of the FAQ's PDF file to be found in the New Collector Forum you will find a listing of the parts which should have the serial number. On pages 62 and further are diagrams showing what the parts look like. Very nice that the owner wants to break it down for you- that's unusual.... so would be good to watch the process and ask questions.
(link here below- pdf at the bottom)
http://forum.lugerforum.com/showthread.php?t=13121
Is there only one magazine? There are usually two.... The magazine serial number is on the bottom of the base. An unmarked mag could well be the spare. (Experts out there- please correct if needed?)
Anyway- $1500 seems quite fair.... if indeed all matching and good finish, good bore.
Perhaps you should look at the finish very carefully- if it has been stored in the holster "for decades" - the finish may be compromised.
Any information on provenance and history of ownership would be useful of course. Why is this collector selling this piece?
Another question, Are you considering buying this gun to start a collection? or because you want to shoot it?
Reason I'm asking is that I bought my first Luger late last year to shoot, but my gun turns out to be more of a collector's item. Details here below, if you like:
http://forum.lugerforum.com/showthread.php?t=36379
So I was confronted with the question of shooting a collector's item.... is that a "good idea" or "rather not?"
That question has been dealt with extensively, with many Luger enthusiasts on both sides. Threads for your consideration here below:
http://forum.lugerforum.com/showthread.php?t=36411
https://thefiringline.com/forums/sho...highlight=poll
Good luck on your first of probably of several more Lugers !
(Since then I have found a nice shooter)
http://forum.lugerforum.com/showthread.php?t=36454
Enjoy yourself