I got gilespie paint from Second Armor Productions and asked them the same question. Was told that the best they knew of was Painters Choice [if I remember correctly] sold by Home Depot / Lowes building centers. It's their cheap grade of rattle cans. I used semi gloss white with Rick Larson stencils and it turned out great. Apply 4 or 5 very light coats until you have a good solid color and you're good to go. The base color [Gilespie] should cure a couple weeks before stenciling. Btw, they said not to use krylon brand spraypaint. Nothing against Krylon, it just won't work with Gilespie paints. Hope this helps.
Ron