As used in this subchapter, unless the context otherwise requires, the cost-plus-a-percentage-of-cost and cost-plus-a-fixed-fee system may be used under the authority of the State Procurement Director when:
(1) There exists no other economically practicable price arrangement to secure the commodity;
(2) A cost saving may be proved over the least expensive alternative; or
(3) The pricing schedule involved is tied to an industry standard or other reliable system of cost prediction.