Best place to get missing parts

I've just won an ebay auction for a broken iBook 1.2 GHz G4 12". The seller has stated that it is faulty, the screen went multicoloured, then stripy, then black and the fan came on. Sounds to me like the logic board graphics memory fault which should be easy enough to fix with a soldering iron. However he has stripped out the memory, harddrive, combi drive, modem and wireless card. I can get my hands on the memory and harddrive easily enough but does anyone know the best place to pick up a combi drive or super drive for fitting into a G4 12" in the UK? I assume it will be a slot loader which aren't so common anywhere. Also does anyone know if the G4 12" will take an Airport card or does it need to be Airport extreme, and if it does where to get one?