Two part automotive paint seems to be your best bet these days. The upside is that most automotive paint stores can match a color sample and the catylized paints are pretty tough. The down side is that it is expensive and doesn't come in a spray can. I really liked LustreKote for its fuel resistance although it could be sensitive to surface preparation. I presume that this is for a glow powered plane covered in monokote. I've heard of Rustoleum on glow models but have only used it on petrol powered planes myself.