Try eBay. I got the orange one for the original macbook for my al mac book.
Love Zeroshock cases.
P.S. if I keep the mac book, I am going to take the foam out of the original box and put it in the case to make up the small height difference between the plastic macbook and al macbook for the zeroshock. Also because it has a zippered side, you can stuff things in there to make up this slight difference in height of the cases.