It looks like one of the thousands of .30 (7.65mm) Lugers imported into the US after WWI, and known as the "1920 Commercial". Most were ex-military guns rebarrelled because Germany was prohibited from making guns in 9mm. It has commercial proof marks, not the normal military markings.
Actually, it appears to be in good shape, and is probably worth around $1000 or so retail. The "original" grips are American (Franzite?); the wood grips may be either original Luger grips or repros, but they look good and fit well.
As to the "Pearl Harbor" silliness, I think the guess about a Honolulu pawn shop was probably on the mark.
(FWIW, there was a rather widespread belief among racist Americans that the Germans DID bomb Pearl Harbor. Some yahoos just couldn't believe that the "slant-eyed, yellow skin blankety blanks" were capable of planning and carrying out the operation, so it must have been blond, blue-eyed Germans - enemy sure, but a "worthy" enemy.)
Jim