So as it turns out the 570/650/675 generations have 380x34 carbon ceramic rotors on the rear and they sell for cheap online. Would those work for our cars with the caliper spacer on the regular calipers? Offset info is hard to find.
Using this link it seems the RS5 front rotor offset is 11mm.
And this link shows the 650 CC rotor offset seems to be 10.6mm.
At best, the already available caliper spacer and CC spec pads are the only necessary additions. At worst, we find a 10-bolt hat with the correct offset and diameter. Am I crazy or will this work as a super-low-cost front CC with OEM caliper?
Also a potential problem seems to be the CC rotor has 82mm surface, the RS5 is only 64…not sure how to address that yet. Edit: the rear 650CC pad is only 62mm surface. RS5 are 57mm. I think pad contact is much more relevant than surface diameter.