My other car is a MINI!!!!
there is a difference between the 2wd and 4wd 256mm vented brakes, but I'm not sure if it's in the caliper or the carrier. I know when using the rears from a 4wd car on a 2wd car a spacer is needed to ensure the correct offset.
If it's just the carrier that's different though, you can get teh calipers from any 2002> 180bhp golf gti, seat leon cupra's, cupra R's, most TT's, octavia VRs, R32.
Anything based around the 8L platform that uses 256mm rears as standard.