I took it to a garage this afternoon and he said he will strip back the cable and fit a new plug for the same price as a hole new one
Il do it when im off on thursday.
By the way, that coil on ebay looks pretty much identical, its off a 4stroke 50cc kymco so it should be the same engine?
The old Cap and cable still work but its getting full of crap and probably not sparking like it should.