How about another item to help you learn really fast at a cost?
Lexicon of Learning
Wondrous item, rare
This small folio printed on silvery parchment with near indisipheral text. You must have training in survival, religion, history, arcana, medicine, or nature. If you spend an hour reading the text, a portion will start being something you can understand but that will fade and another section will be compressible. If you spend that time, you choose one of the listed skills you have, lose proficiency in that skill, and gain proficiency in a different skill from the list. This last until you spend another hour using this book again.
Thoughts?