My unqualified thoughts, realistic range $5 to $30 although it has some fine detail and if you auctioned it on eBay, all to takes are two keen people and it could push up to $100. I would recommend full disclosure on any cleaning to avoid buyer issues.
Nice coin, would have loved to pull it out of the ground......and clean it.....as I like them clean and shiny as they have more value to me in that state