Hi and welcome to the site! I'll take a shot since no one else has answered. We can probably divide this into 2 parts... value of the book and then what additional value the signature adds.
The book itself is fairly common, and you can find approximate values on this page (
Rulebooks Index) near the bottom. So probably around $5-$20 depending on condition. Now is the addition of Easley's signature worth anything? Maybe a little more, but not alot. Mr Easley is still with us and attends a number of industry conventions so his signature on something is not particularly rare. But potentially worth a few dollars more to the right buyer, especially if the book itself is in top condition i.e. a collectible-quality copy instead of a play copy.
