My girlfriend purchased seasons 1-5 for me off of eBay for around 80 bucks.

I'm pretty sure they're bootlegs, as the boxes they came in aren't the ones found in stores (although they do match the designs), and the discs came in little slip cases. But they all worked perfectly fine...and for 80 bucks (or hell, even 120 bucks, like DSC payed), you can't go wrong.