There shall be paid to each of the port commissioners from the funds of the district, not more than fifty dollars ($50.00) per day for each day spent attending meetings, or while engaged in port business authorized by the port commission. In addition, such commissioners and the agents and employees of the district shall be entitled to be reimbursed upon order of the commission, from funds of the district, for all reasonable sums expended by them in furthering the business of the port.