I quickly checked the recently completed auctions on Ebay and prices ranged from $415 - $600 for 30lb containers of R-12. Some of these include shipping, some will require an additional $50 S&H.
I like to scan http://www.refrigerantsales.com
for quick pricing checks. Last I looked, they were offering R-12 at $655, shipping included.
Now you know why everyone is charging with hydrocarbons
No, I'm just kidding, I don't want to start that discussion again, I didn't even bring it up, let's not talk about it.....