yeah 2 piece..is it a 2 piece Kit ?? Defo try a 3G supplier mate
3G were crap when I contacted them and the discs aren't cheap! The very first kits were either 288mm or 300mm if you had the larger ones, the kits later changed to 285mm which I don't think were 3G.
If you measure the pcd of the bell mounting holes you may be able to find another supplier for the discs too.
As i said in my PM, you will get them from somewhere, you will just need to go fishing for them once you know the sizes needed.
Diameter, Thickness and PCD of the mounting holes.