I know rick is cheap but 10k seems unreal for that fragment. In 1980 Along the Columbia River in Vancouver, a boy discovered $5,800 of damaged twenties from the cooper ransom. Sounds like fragments should be easily available, but I guess im underestimating the amount of currency collectors.
https://arktimes.com/news/arkansas-r...-b-cooper-cash
https://youtu.be/Zmr39RWVjzQ