Order it directly from kgcoatings.com, they are nice folks.
Like everyone says, prep is key. I've heard the you get best results from applying it over parkerizing; but my experience is that grit-blasting (NOT glass beads!!), then a hot water rinse (to get any dust off) then into the oven to warm it up to about 50°C, then super-light coats. You want to almost see the base metal through the first coat. Let the solvent flash-off and re-coat. I usually went 3 of those super-light coats, just enough to ensure good coverage.
Baking can be a challenge; but you can bake one end of a rifle and then flip it over and bake the other. Baking part of the coating twice doesn't hurt it.