Funny you should ask, it literally belongs to "Shaggy, Scooby, and Velma".
http://www.geocaching.com/profile/?guid=78...d4-6627905198f1
After discovering the coin, I emailed to ask about trades. They mentioned it might show up on Ebay or more likely on the Hogwild auction site.
Like others here, I grew up watching Scooby Doo and loved the coin as soon as I saw it!