Very nice find! George Raver was a saloon-keeper in 1900 in Custer. The token is not listed in Miedema's SD Tokens book nor is it on tokencatalog.com - it would be great if you could post it on tokencatalog, or give me permission and I can do that. George was born in Nebraska in 1862 and died in Custer in 1930. He is buried in the Custer cemetery. It is rather unusual for a saloon to use $1 tokens - they usually used 5¢, 10¢, and/or 12½¢ ones. My guess is that the token was used as a gambling "chip" in card games.
John in the Great 208