meet the Herold/Postman

The Herold is a villager that spawns like the Trader near the bell. You can give him a signed Book and an amound of emeralds (for every Emerald he will hold on to the book for another ingame day max (64)). Or buy previously given signed Books for 5 Emeralds.
If there is a named Chest near the Bell with same Name (or maybe same first 8 Letters) as one or more of his signed Books, he will put a copy of those books in the Chest (maybe only if he can take the right amount of emeralds out of it).
Maybe all Herolds share the same inventory and at least once a Moon cycle one spawns in a village.
The max on books he can carry is limited. If someone needs him to make room he can pay 10 Emerald blocks to get the final copy.
How long a book will be in his inventory is visible on the storepage by the book.
He would stay for one or two days in a village and could share gossip from an other town (if that is possible)

This mechanic would be great for immersion and roleplay, but could also be used to keep people updated on changes, events etc.