For $200, you have lots of wiggle room to do with what you want - shoot it or refinish it.
You can try to polish it lightly and see what happens. Like was said, when you see rust on top of nickel, it's usually coming up from underneath. A bad sign.
In this case, since your purchase price was so low, you could get a fantastic refnish job and still come out even or ahead. If you want it re-done, and you are in Tampa, let me tell you what to do. Set aside a nice day to take a pretty drive up to Crystal River. There used to be a great restaurant on the water there, but I can't recall the name. Anyway, drop it off at Ford's and then wait for them to mail it back to you. You will have the finest re-finish obtainable by man and at a fair price. "Breathtaking" is not too strong a word for some of their work I have seen. I would guesstimate a Ford's nickel re-finish on a 58 would still make the gun worth $600 or $650, so you'll be comfortably safe. A less high quality re-fnish would not be worth as much.
Cogan Custom/APW used to be in Safety Harbor (I had them do work for me), but now they have moved to southern Alabama.
The advantage of having someone local/semi local is you don't have to pay $40 to $80 to ship it with the BATF, USPS, FedEX and UPS shipping restrictions. Ford's can mail it straight back to your doorstep since they are an FFL holder. The money you save outgoing will equal the cost of gas and a nice lunch up there, and it's a pretty drive (or it was 15 years ago the last time I did it and it wasn't all strip malls yet
). Plus you can meet them and he can give it a look over to see if anything else might be amiss or require attention.
Wow, a 58 for $200. If he's got more, send me a pm!