There are varying companies making kits of stainless bolts for the SV - can't remember any names off the top of my head though, I'm afraid!
Also I seem to remember Chewy22 on this site was making kits for them too and people seemed to be quite impressed with these... I'm sure if you search through the Tuning & Tweaking section you'll find a post about them!
As for preventing the corrosion, the only real way is lots of washing!
I used to wash mine down with my jetwash after every use in the wimter (before it was wrecked!) and this helped a lot... I never got to try the FS365 spray I bought before it was written off but I used to just use WD40 last year... Does smoke & smell a bit as it burns off the engine though!!
HTH