OK, so I found this over the weekend..
It says Pengo 1-4 on it but when I fired it up.. it is the 1983 first version according to www.atariprotos.com Here are some screen shots.
Everything appears to be legit about it. I don't want to breach the label to open it up though. It is heavier than a normal 2600 cart. Any ideas what this is worth and does anyone know if any others exist? I have looked online and saw that someone had a copy of the 1-4-84 version but I didn't find anyone to have this first release. I am looking to sell it if the price is right. Is this the only known copy?