2.0TDi rear calipers upgrade

Hi guys! Recently I purchased Mk7 R front and rear calipers for my O3 2.0TDI DSG pre facelift but realized that it actualy has mechanical handbrake rather than electric (im a dumbass I know). So is there any direct fit for bigger rotors like 312mm and mechanic hand brake?

Or maybe something a bit smaller? Im planing on 19" summer setup so dont want too small rotors on rear end.

And is it absolutely neceseary to have dust shield covers as It seems that I cant fing them for front or rear :-(

Thanx for any info and help :-)