Here's an idea for your code store. Quill of Hording, or some such name. Purpose is to change rune books to 50 charge runebooks. It should have around 300 charges initially (rechargeable at a scribe in town)and uses one charge for each charge it adds to the book, so that a 20 charge runebook would take 30 charges when used but a 10 charge would use 40. It should be a $9.99 item.