I bought mine brand new from Ed Morad. His are not the GM ones, but they are exactly the same and come with a lifetime warrenty. Cost is about 100 bucks per side plus shipping.

If you go that route, make sure you put your old ones in the box the new ones came with and save them. If you ever have to ship them back to Ed, you will have a box to ship them and a headlight to use until your replacement comes in.

webracin