inexpensive OIL based paint?

Recently bought a used 16' cattle trailer, pressure washed it, welded in some new panels, and now I need to paint it.
I've got some thick Alcatraz fence paint for the floor, but IDK if it will bight to metal. I want to paint the entire outside as well as most the inside. I'm looking for a thick, black oil based paint. And don't tell me Rust O leam, because it cost like $40 a gallon. .

?2014-05-11T22:55:50Z

Honestly for exterior oil paint $30 is about as low as you can get, you will have to check in your local stores for brand names but either Ace, True-Value (other hardware stores) will have something that you can use. I don't remember the brand name, it was in a green and white can (probably a store brand), I painted my mother in laws carport roof with it and it's held up for 7 years without any peeling or cracking (only stores around here that sell paint are True Value, Walmart, Sherwin-Williams). She is very cheap and spent something like $28 gallon which probably means that is as low as you are going to get. You might have some luck checking with local stores and seeing if they have any mis-tints (usually 25-50% off) and have them tint it black.