He really is the guru of all things Walther. He has always been the man in US for the old Walther stuff. I've been out of this stuff for a while, but IIRC, at one time he handled all of the Walther imports and service for Walther USA or maybe S&W. I don't know if it is still like this today but when you called Walther USA with a question they would usually tell you to call Earl's.
Walther Firearms and Accessories, Earl's Repair Service Inc. - Home Page