Herb,
Thanks for posting the photos, the gun is very interesting.
There was an informative Bulgarian Luger thread on another Forum, you can find it if you follow
this link.
Your example is heavily buffed, and I feel it safe to say that such buffing would have removed any numbers which might be present anywhere on the exposed blued surface of the gun. The numbers which are present are unexpectedly sharp. The number on the takedown lever is in a different typeface, and looks partially buffed away.
I would hazard a guess that this Luger's serial# originally ended in 02, and that the buffing process necessitated the creation of a completely new serial number, picked essentially at random. It would be interestng to see the number stamping on the trigger and the internal parts.
--Dwight