Unopened would be a fair bit rarer, though. I still have my gold cart edition, complete in the box, but the box has... definitely seen better days.

A quick look on eBay.ca only shows five auctions for gold carts available at the moment, and only one of those is complete -- although the seller is a bit of an idiot, thinking he can get 990 euros for it.

The rest just have the cart, and are averaging around $40.
Not sure what's up on eBay.com, since I never go there... get disappointed too much when I find out they don't ship to Canada.