The rules of each agency board shall include a procedure for the expedited disposition of any appeal from a decision of a contracting officer where the amount in dispute is $50,000 or less or, in the case of a small business concern (as defined in the Small Business Act [
15 U.S.C.
631 et seq.] and regulations under that Act), $150,000 or less. The small claims procedure shall be applicable at the sole election of the contractor.