If it appears to the chief officer of police that—
a person required to be registered as a firearms dealer carries on a trade or business in the course of which he manufactures, tests or repairs component parts or accessories for shot guns, but does not manufacture, test or repair complete shot guns; and
it is impossible to assemble a shot gun from the parts likely to come into that person’s possession in the course of that trade or business,
the chief officer of police may, if he thinks fit, by notice in writing given to that person exempt his transactions in those parts and accessories, so long as the notice is in force, from all or any of the requirements of section 40 of this Act and Schedule 4 thereto.