cheap primer for a spray gun

I found some affordable epoxy primer a while back. When I did the cab corners, rockers and door skins on my ram. I didn't want to spend a fortune painting it but I wanted it to stick so I got this cheap epoxy primer I think it is called t rex or something ill find a photo but it was only 39 dollars a quart with the catalist from Amazon.
I found it in my orders its speedokote T rex. Its sprays nice I think it sprayed just as good as the more expensive epoxy primer.