If you haven't made it over to the "MACHINES" link yet you can look up each game there for more info. There is a price estimate about half way down with a link to archived ads.
Unfortunately there is not much info on Magic Circle as it's an older game that is pretty rare. Condition is key on pricing with the playfield and backglass being most important.
There are some Pinsiders on the east side of the state that would probably be willing to take a look at them and interested in buying. I'll be heading to Flint once our order is lifted and would be willing to check them out if needed.
Good luck! ~ Matt