30. Making of contracts through agent.
(1) A contract (including a contract of employment and whether in writing or otherwise) by which any election expenses at an election exceeding £500 in value are incurred by or on behalf of -
(a) a political party pursuant to section 32(1)(b) or 33(1)(b), shall be made by the national agent of the party and shall not be enforceable against the said party or the said agent unless so made; and
(b) a candidate at the election, shall be made by the election agent of the candidate and shall not be enforceable against the said candidate or agent unless so made.
(2) Nothing in this section shall prejudice the right of any person who is a party to a contract to recover from any other such person any moneys, property, goods or services due to the first-mentioned person on foot of such contract.