I agree with William, the best way to find an old part is to call the Chevy dealer parts department or General Motors, they advise where to a part or an alternate part the would work.
This is a corvette 1982 stingray. Does it help?
I'm sorry I don't have any knowledge about that but I recommend calling the dealer. It should be helpful if you said what model Chevy he owns. Chevy never really had exclusive cars at that time. There is usually models in the other brands GM owns that use the same parts. GM owned, back then, Oldsmobile, Buick, Chevrolet, Pontiac and Cadillac.
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