(a) A justice of the supreme court, a judge of the court of criminal appeals, or a justice of a court of appeals engaged in the discharge of official duties in a county other than the justice’s or judge’s county of residence is entitled to traveling and other necessary expenses, as provided by Chapter 660.
(b) A justice of the supreme court, a judge of the court of criminal appeals, or a justice of a court of appeals is entitled to receive from the state the actual and necessary postage, telegraph, and telephone expenses incurred in the discharge of official duties.