Ich werde entsetzt!
(How did I do remembering my Hoch Schüle Deutsch?)
Sunburst with double-white binding is a desirable thing. While I won't hit you with a Regenschirm, you will understand why I am scratching my head.
I am sure that you could airbrush over it. You wouldn't be painting the binding though, you would just be painting over the clear coat that is over the binding. Without clearing over you airbrush working, it would probably be hard to make it stick.
May I suggest finding a non-bound sunburst body and swapping them out?
Willkommen zum der TDPRI!