You can get them many places. Expect to pay as high as $800 for a first run quality model that needs very little work. The Whitney hood is fine, and a great price, but if you are going to paint it a dark color be prepared for many hours of hand blocking, priming, skim coating, and guide coating to get it right. The air chamber underneath for the ram air is usually a seperate item. I bought my hood second hand and it was already in there.
I have seen used ones with slight damage at virtually every large Corvette show I have been to in the last couple of years for $100 to $300.
You will be after the L88 hood with the long design so that it goes all the way to your windshield.