Power Steering Pump and Fluid

[Chambers]

Hi all, my power steering pump is starting to take a dump, it has destroyed three belts in the past four months and its now making a quite undesirable knocking sound. So I was wondering where should I look for a new pump, is the dealership my best bet?

Since I'm planning to get a power steering pump I will also fix the current leak, since it wont be leaking I will be able to run a higher quality fluid in it, so what type of fluid do you all recommend?

Thanks.