(3)In particular and without prejudice to the generality of the foregoing power, such rules may-(a)fix the price at which postage stamps shall be sold;(b)declare the classes of postal articles in respect of which postage stamps, shall be used for the payment of postage or other sums chargeable under this Act;(c)prescribe the conditions with regard to perforation, defacement and all other matters subject to which postage stamps may be accepted or refused in payment of postage or other sums;(d)regulate the custody, supply and sale of postage stamps;(e)declare the persons by whom and the terms and conditions subject to which postage stamps may be sold; and(f)prescribe the duties and remuneration of persons selling postage stamps.
