Mine are knackered too. Explains why the fan doesn't work... lol You might possibly find that someone makes a replica connector, or that Honda actually sell them. Some while ago, somebody posted a link to a genuine Honda repair kit for the alternator connector, although it cost a small fortune!
You can buy spades on eBay or from Halfrauds, etc. You just need to measure up to make sure you get the right size as there are lots of different sized spades. It doesn't help that some are sold by wire diameter, while others appear to be sold according to the size of the female spade. Persuming it's the wire end of the spade that's corroded, I'd take what's left of the thing to Halfords and compare against what they have.
Failing that, if you're not worried about keeping the original plug, just get something like this and bin the current one. I've used a few bits from this source, and all seems well so far.....
http://www.ebay.co.uk/itm/2-Way-T-Elect ... 1e78ab86e2
. Can somebody point me in the right direction, ebay or something ?? will need a crimper as well i guess ?? 
