Rear discs and pad s3

Do you really mean OEM,or a set of replacements?

If the latter,think about Mintex 1144 or 1155 pads,and I've just replaced the worn out discs on mine with ZeroSixty discs.

I'm a big fan of Pagid for OEM replacements.
Their painted discs stay looking good through the wheels too.
Only the service area of the disc rusts after
for example washing the car. The hub and edge stay largely rust
free for a very long time. On my last car there were no signs of rust after
18 months. Very happy with that. Can be bought from ECP for reasonable price.