OK. After a bit of a check around, and some chatting with Mike from Camskill, and a bit of part number searching and comparison, Mike from Camskill has been able to supply me with two upper arms (wishbones), with bushes and balljoints. The good bit about these replacement parts is, the balljoints are held in by a large circlip, (they are pressed in, but not with a huge hydraulic press). So the next time the upper ball joint goes, it is only the balljoint that will need replaced.
I will attach some photos below (hopefully). The parts are identical, and a perfect fit, I have had them on for a few days now, all good.
Mike is getting more in, and they will be available on the Camskill website for £79 each, inc vat.
The mitsubishi cost was £177 plus vat. so definitely a better deal