Starter?

[superdave555]

when I started my car for a couple of times it kind of made a bit of a grinding sound but started up for a couple of days, but now it makes a whirring sound coming from the starter. When I bought the car it had a fairly shot battery and I haven't gotten around to fixing it. does anybody have an opinion as to whether it's the starter or whether it's not getting enough juice? I fear it is probably the starter.

also, can someone give me a starter part#?
92 svx l