The official reporters of the court, if otherwise eligible, shall be members of any retirement system maintained by the county that includes attachés of the court. For the purposes of such retirement system, the salary or compensation provided for reporters in this article shall be deemed their entire compensation, except that where credit is claimed for service rendered prior to the establishment of such salary or compensation, the actual compensation paid to them by the county shall be the basis for contributions for such prior service, and continuous employment of the court, prior to membership in such retirement system, shall be considered as “prior service” therein upon the payment by the reporters of the sums due, if any, under the retirement system.