Condition is of utmost importance with laser discs..... I suggest you find a player and test the game in its entirety, play it all the way through.
Laser discs can have laser rot and it's something that doesn't always show up physically on the disc so watching it will determine if its succumb to rot.
I've bought discs from $30-$100.... with today's economy, and providing its not rotted, you should be able to get $50 for it.