You could probably get about $50-60 for each of them providing you have the game, booklet, maps, and advertising stuff that came with them. I'm assuming they're all in good, but not mint, condition.

If you just have the cartridges, you could get... around $45 I'm thinking.

Complete sets usually go for around $100, and I've yet to see a factory sealed one.

What is it they say about silence being golden?