Such city may appropriate and utilize its revenues and other available funds to contribute to all or part of the cost of such plan, including payment of insurance premiums, for furnishing all or a part of the medical, hospital, and life insurance benefits provided under the plan for its employees, and comparable benefits for employees who rely solely on spiritual means through prayer for healing. Any participating public employee whose compensation is not paid by such city from municipal or county revenues may not have premiums or pro rata costs paid therefrom, but such premiums or costs shall be paid from the revenues of the participating public utility, board or agency employing such employee.