I'm not sure you will be happy painting a plane that size with an airbrush. I use one on tail surfaces and ailerons, but it's difficult to get an even finish on larger surfaces.

I purchased a touch up gun and have done my spraying with that. It is very easy and leaves a nice smooth finish.

As far as paint, I would look at Nelson Hobby Paints. They are waterbase and fuel proof. Best of all, they don't have any odor. They can mix any color you want - just send them a photo.