epoxy primer_buy on Ebay????
I buy all my paint and primer online. For primer products and urethane reducers I use
http://www.southernpolyurethanes.com/
Check out my build thread in the signature below(or their site) for some of the uses. Their epoxy kicks ***, be sure you neutralize that acid with plenty or water prior to sealing it up with epoxy. The only products I am aware of that are to be applied directly to rust for encapsulation are POR-15 and Rustbullet. These are thicker products that work great on the undercarriage or hidden areas.