There are places that sell that expensive stuff in small quantities. Try this one:

http://coastairbrush.com/pages/45.html

Also look into the acrylic's from Createx and others. Try this link:

http://www.createxcolors.com/product...ush_colors.htm

Much cheaper ($16 for 16oz), non-toxic, cleans up with water. Still has to be clearcoated to be fuel-proof, but so does the expensive stuff.