As a regular visitor to shopping warps, I suggest that you place an item frame with the item you are selling in it close to the chest shop. In the case of enchanted books, you'd better take one of the books and rename it before put it in an item frame because the item information is just a code, it doesn't specify the details of the item. The same thing can be made for potions and banners.
PS.: Each enchanted book has its own code, and it changes in accordance with the enchantment(s) inside the book.
For example:
403#jn (sharpness 3 + slowness 3 + hunger 1)
403#jo (sharpness 3 + hunger 1 + venon 2)
403#jp (sharpness 3 + lifeleech 1)
In such cases, 403 is the code for the enchanted book.