Musical Fidelity A1 I

What is cost to have repair center recap and replace volume knob on an A1 amp? And what is a fair price in that amp? The volume knob is missing and much of the lettering near the control knobs has worn off. Should I maybe look for a newer model with less wear? I need an amp $500 - $1000 used or new for Triangle Altea ESW speakers and Oppo 105. I want to make the right purchase so Triangle's sound good. Thanks! P.S. I know squat when it comes to hifi gear, systems, etc. Do I need additional gear to play my CDs and SACDs?