Mike, I can't believe you made me look through every page in the book when you had the model # all the time!
OOPS! My bad, I just enlarged the pic of the pile side and there's the number plain as day!
OK then, other than possibly the illustrators getting things screwed up, the only thing I can think of is perhaps this is a transition piece. That knife is shown as available from 1921-1923 (a very short time period!). Winchester bought Walden(Simmons Hardware cutlery division) out in 1922, and moved all equipment to the Winchester plant in Connecticut. They then began producing Keen Kutters there in 1923. Somewhere along the line the nic was changed, from what to what I don't know. Another possibility is that blades from other models were used if things were running short during the move, and stamped accordingly. These are all just humble guesses on my part, although I definitely think it has
something to do with the transition. I'd be curious to see if the nics changed on that bone model below it since that one ran to 1938.
Eric
! I couldn't get my credit card out fast enough! Mint but for a little spider web, it's uncarried and unsharpened. 
those are uptown upnorth!!! i like the sawcuts in the bone, nice examples 
