There are threads here on changing your plug wire, it's quite easy to do. A quick search here will get you all you need to know. I'd never done one before and it took me 5 minutes on the first try. It depends on how well the CDI was made as to how much fight it'll give you. The first one I did, the plug wire simply unscrewed from the CDI, the second had been thoroughly glued together, and was a pain in the ... neck. In both cases, the factory plug-boot died of shame, just fell apart on the work bench.
The best place to go is your local NAPA store, buy a length of solid core plug wire (or coil wire), a plug boot, and a couple of plugs. I'm using an NGK B5HS with good results, but others here may be able to recommend something better for you.