If anyone still is looking for a lighted cover for their 350 reader, here's a great deal for $14.75 plus $3.75 shipping for new covers in blue. I just bought 1 (I already have one and I love it), I don't expect they'll last too long at that price. They're usually selling used for over $60.
eBay link to blue covers
Edit: Seems all 5 covers are now sold.