I use Evercoat primer (in the summer here I use common lacquer primer...way too hot to use catalyzed primer and the old style stuff is a bit less $$$). As for body filler, it is expensive but I use Evercoat Easy Sand (think it is part number 421). Last catalyzed primer I got was something like $210 a gallon...last lacquer primer was maybe $180 a gallon. Cut the lacquer 1.25 thinner to 1 part primer in the summer and a nozzle of around 2mm. Good luck.

~ Jon
1952 1/2 ton with 1959 235 | T5 with 3.07 rear end