No need to post again. Your question will eventually get answered, but tires are one of those things where there's not a ton of info on.
As for which tires would be "correct", the 68 Camaro was fitted with several different sizes and manufacturers with the main three being Goodyear, Firestone and Uniroyal.
From your post, it appears you're looking for the Goodyear like the one pictured below. (Note that this is a 1968 Z28 tire, but the SS tire looked the same, just a different size.)
Ed