No such serial number in the PPK/S range.
No such sn in the Walther convention
You will have to contact Walther
You will need to contact Walther to find out.
1961
Dieter Marschall's book on Walther has sn data in it.
Try asking on the p38forum.com
Try the P38forum
You might have better luck on P38forum.com
Someone at the P38forum.com should be able to help
Someone at the p38forum.com will probably be able to help you.
Someone at P38forum.com might be able to assist you.
Might be listed in Dieter H Marschall's book.