Stainless bolts are a good replacement if you're taking them out, as these won't corrode in place and cause problems later.
You can buy them in sets off eBay for about £15, but I would advise you to search for the right size bolt on eBay instead and pick them up for pennies!
eg:
http://cgi.ebay.co.uk/Stainless-Alle...cmdZ ViewItem (don't know if that's the right size though - Nelly will tell you!)
I've used Tek Hardware before off ebay and he's been great.