Thanks for being a guinea pig Kernon! DiapDealer made a joke about the ASIN number of a toaster being workable for this trick... looks like he may be right.
Karma comin' at cha!
It looks like you have a good fake numbering system. My concern is making sure the fake number is not one for books we already own or might buy in the future. I'll stick to the ASIN of a pbook version but try a fake number if I can't find a matching ASIN.