Section 101A. The commissioner of probation shall establish uniform forms of blanks and records for use in the probation offices of the district courts, and, upon receipt of competitive bids, the state purchasing agent shall order, at the expense of the commonwealth, and maintain such supply of said forms as the commissioner of probation shall determine to be necessary to meet the requirements of all such offices. The commissioner of probation shall from time to time distribute to the district and juvenile courts such quantities of such forms as he shall, with the probation officers of those courts, determine to be necessary. No forms of blanks and records other than those established and furnished hereunder shall be used in such probation offices unless approved by said commissioner.