Where tax has been collected by any dealer in the State on any sale effected under this Act to any official or personnel of,-

(a) any foreign diplomatic mission or consulate in India; or

(b) the United Nations or any other similar international body, entitled to privileges under any convention to which India is a party or under any law for the time being in force; or

(c) any consular or diplomatic agent of any mission, the United Nations or other body the tax so collected shall be reimbursed to such person, mission, United Nations or other body in such manner as may be prescribed.