My favorite places for farming pristine hides are the bears just outside of Thorenhad. (just south, and another group just east) and they all respawn pretty quickly. The coords for those ones are 32.2, 15.2 and 32.0, 14.6
and another place I really like is the wolf den, Drauglad (which rocks because the wolves count for a deed in trollshaws anyways, if you haven't done it yet) which is at 35.0, 13.9. Hope this helps!