Copy over the original one in the RIVA installed path (C\ProgramFiles\Riva).
Btw, you never mentioned how far you want to clock the card. AFAIK the slider went to 1000 core in AB, so for air is enough. For more, open MSIAfterburner.cfg and set UnofficialOverclockingMode to 1.
Try Sapphire Trixx to, has unlocked sliders