I need my power steering fixed, though I am not sure if I need a new pump. It could just be the belt or the screen.
In this situation I would suggest getting a mechanic to look at it for you. This way you can avoid replacing parts you don’t need. If your system is making a type of moaning noise, if could be a pump or simply low on fluid because of a leak. If the belt is screeching when you turn, it could be low on fluid, a bad belt tensioner, a rack and pinion that is leaking internally, or a pump that isn’t developing enough pressure. Having someone inspect it will save you money in the long run.