This is a K date Luger, serial # 10000.  Most books claim that Luger's and P.38's were serial numbered from 1 to 9999 in a letter block and then started over with 1 in the next letter block.  This K date and a P.38 in my collection are proof that the numbering actually went to 10000.  This would make sense because it would be more logical to keep track of the number of weapons produced.  There is also a 1937 P.08 in Kenyon's book Luger's at Random that is serial numbered 10000.  You may ask why more 10000 serial numbered Luger's or P.38's have not shown up. How many of ANY one particular serial number have you ever seen?

This gun is all matching except for the magazine which is # 550a and has the correct K Date proofs.