It looks to be the air cleaner that I need.
Is it for sale?
Unless someone sees some detail that I have missed, it appears to be a 1967/early 1968 A body 383 air cleaner.
http://www.nicksgarage.com/aircleaner.htmAccording to Nick, about a third of the way down the page, it was also used on early (early not defined) B bodies.
If it's for sale, let me know. I'm sure the people here will help settle on a fair price. I know it's in the hundreds.
Bob