Personally, I’d pass it up. I got one brand new factory sealed in perfect condition for only about 40$ on an eBay auction, which I guess is about the average price for the game in complete condition if you buy it through an auction. There’s none on eBay, half.com, or amazon.com right now confirmed with box and manual for cheaper, so, if you can’t wait a while… then go ahead.
$50 is about an average deal, considering the box is squished. This deal has probably passed, but I’m posting because I just bought a copy of Nester’s Bowling for $20 without the box, but it came with the instructions.