If my memory serves me right, The latest Egon's lab available on eBay did sold for $750. I might have the buyer's name somewhere but then again, I doubt that he'd be willing to part with it.
I'm wondering if Greg (from late Gbdetroit.com) has one. He bought a lot of original paintings, sketches and proof cards from me a few years ago. A great guy and a serious collector.
I personally prefer the production pieces to the unproduced stuff. Original packaging paintings are by far my favorite. I'm often thinking about that Slimer painting that I barely missed and that Ecto-1a painting that sold on eBay for a low $250 (Damn you Mr. Flarida!! hehe)

Anyway, good luck with the hunt for protos, you never know what and when a new batch of protos might surface. Keep you eye (and wallet) open

Google these guys:
-Toy Heaven
-Hollywood Heroes
-The Earth Toy mall

Best regards

http://archive.ghostbusters.net/article/64/

Hey Bathalon,

Thanks for the leads. Is there any way youd be willing to ask your friend about parting with his? Also would you happen to have Greg from GBdetroit.com's contact info that you can PM me?

Also, do you have any proofs youd be willing to sell? I am very interested!

Thanks a lot bathalon, obviously i'm interested too about the guy's infos. If you can let me know. Thanks again!