The Commonwealth is liable to pay compensation for the cost of treatment obtained for a person's injury or disease if:
(a) the person is entitled to treatment under Part 3 for the injury or disease; and
(b) the person obtains the treatment before any determination by the Commission that the person is entitled to the treatment under that Part; and
(c) it was reasonable for the person to obtain the treatment; and
(d) a claim for compensation in respect of the person has been made under section 319.