MEK is not a carcinogen as is one of the safer solvents to work with. I've worked with MEK for over 20 years. I am a Chemist and have worked with and kept up with MSDS info on most organic solvents over the years. You can buy it at Lowes and other hardware stores in the paint section.

MEKP is much more hazardous as it is a strong oxidizer as stated. Many of the hardners have MEKP diluted with plasticizers (DOP, dioctly phthalate or others ) to make it less senstive to decomposition. The plasticizer mixes in with the resin and reduces brittleness.

I don't know why anyone would want to mix all this stuff into model airplane fuel. Just go buy you RC fuel favorite brand and fly!