I know it's discontinued but have you tried your local Chevrolet dealer? They can look in their system and see what dealers around the country show to have it still sitting on their parts shelf. I've done this several times and have had good luck but usually have to call several dealers that show to have it...just because it says they have the part doesn't mean they actually do. Other than that, keep watching Ebay or go get a good used one at a salvage yard.
Good luck!
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