N200 is taken. It's currently assigned to a 2009 Embraer-Empresa Brasileira De EMB-500 registered in Whitefish, MT.
See the full aircraft record →A tail number only frees up if the owner deregisters the aircraft or moves it to a different N-number — and even then the FAA holds it before releasing it to the public.
N200 has been worn before. Past registrations from FAA deregistration records: