Hey Doc,
There's a new company out there that is doing exact remakes of the cherolet emblems SS, Z-28 and some of the MOPAR. They are adding to their catalog every day. I can 't recall the name but now that you know they are available you could do a serach and not give up til they are found.
It's kind of easy to call it quits when you are not sure if a company exists but if you know they are out there it makes the search just that much easier. I saw their products on one of those weekend Garage shows that actually are more about advertising their sponcers than most anything else.
I know you said you found the emblems you were after but just in case you need any others.
Mike