ps pump replacement

[1990LTD]

I hate littering this place with n00b threads full of stupid questions, but I don't understand something about the parts listings on Rockauto. I'm looking at

A-1 CARDONE Part # 20257 {w/o Reservoir; Reman.}
Exc. Police; w/o Magna-Pure Filter

I don't know what any of this shit means but every PS pump on their for my car is similar to this listing. My PS pump is leaking and I want a new one but don't know if this is it.

[andymac0035]

I would think you'd want the one with a resiviour.

As far as I know you can't get a new one, you can only get a remanufactured one.
....or at least that's what I was told at my local parts store. (I replaced mine over the summer)

If you don't have the pulley puller tool, you'l want to get one. (or rent one).