Whining noise in area of power steering pump. Replace or flush? It's a 2008. Probably never been changed. Bought used.
If you're getting a "whining" sound it could be as simple (and easy) as low or degraded PAS fluid. First up: check the level - if it's low then that's a pretty telling give away. If not then it's likely worth changing the fluid anyway just to rule it out.
If the fluid hasn't been changed (or you don't know how long it's been!) then I'd go for a full flush change.
It's possible though that the whine is the beginnings of the pump failing as sometimes the bearings sound like that on the way out. But I'd worry about crossing that bridge if you get there.
If the sound is more of a squeal or screech then the belt is the more likely culprit (assuming your car has a belt-driven PAS pump)