I only know of two, Jim. There is a Low Grip Screw (701341) that was for sale 10 years ago for $10,000 (I took a pass on it back then but it still haunts me today) and an unmarked, unserialized Early Wartime piece with no blueing ("in the white") shown in the book.
Vlim may have seen one in the Oberndorf museum, we'll wait to see what he has to say. On a separate note, both he and I have Cutaway New Models that we take great pride in ... so I can imagine how special a Wartime Cutaway would be in any collection.