If the public defender commission has obtained a judgment against an offender in the custody of the department of corrections, and the offender is later paroled and becomes financially able to pay all or some part of such judgment, he shall be required, as a condition of his continued parole, to pay over to the public defender commission such amounts as he can reasonably pay, either by a single payment or by installments of reasonable amounts, in accordance with the schedule of charges for public defender services prepared pursuant to section 600.090.