You never said V6 or V8, but the valve you bought, EGV672, fits a plethora of L4 and V6 AMC, Buick, Caddy and Chevys. Not Chevy V8. The gasket you have is a Chevy V8.
According to what I can find, I'm assuming you have a 305 V8, original to the vehicle. Your original part numbered EGR valve should have production number stamped on the top of 17075612. The part number in the parts catalog 30 years ago was 17079818. Going through a number of supersessions and exchanges for that valve, including 17113433, it lands as a 19210681 as the latest GM part number. It's your job to verify what you got and what you need. I'm assuming the engine that came in the car was the original 305H.
Best I can tell, this is a non-negative or non-positive pressure valve. Meaning a direct acting one. Your valve should respond instantly to a vacuum signal to open even without the valve being on the car. I'm more used to Olds V8s with the EGR solenoid, and those need to be on the car with the engine running to test with a vacuum signal because they won't respond to a simple vacuum signal when the car isn't running. I've seen people check the EGR's on Olds V8s that weren't direct acting and replaced them for no good reason. They weren't aware the valves were normal when they "leaked air" with the engine not running.
Anyway, here's a GM 9818 one on the bay.
<p>AC Delco EGR Valve 214-5512 (17113433). </p>
www.ebay.com
Personally, I don't care for those aftermarket EGR valves because they weren't calibrated for the engine they were on, as they're engineered to umbrella a lot of different part numbers. You may can tune some of them with the adapter rings, and such, but I'm still a fan of ACDelco emission parts specific to the application. That's just me.
If you want to stay with the aftermarket, Standard makes a EGV435 for the 83 305H engine. If that's what you're looking for.
Free Shipping - Standard Motor EGR Valves with qualifying orders of $99. Shop EGR Valves at Summit Racing.
www.summitracing.com