I found an auction online that has a packaged Mickey Mouse (top pencil in the picture above) with the model number XP565. The X in the model number means packaged, so the model number of the pencil is P565, which is what I suspected a while back, before changing it in the Pentel Book to DP325.
In the next publication of the Pentel Book, I will change it back to P565, and it will be listed next to the Popeye pencil.
Needless to say, I will be bidding on this.