Nothing in this chapter shall be construed to apply to:
(1) The transportation or handling of United States mail; or
(2) The casual, occasional or reciprocal carriage of passengers or property by aircraft in intrastate commerce for compensation by any person not engaged in air commerce as a regular occupation or business, unless, in the case of transportation of passengers, such transportation is sold or offered for sale or provided or procured or furnished or arranged for by a broker, or by any other person who sells or offers for sale transportation furnished by a person lawfully engaged in the transportation of passengers by aircraft under a certificate or permit issued under this chapter or under a pending application for such certificate or permit.