I recommend going front disk Oem (Original Bmw), then the rest you can go for the usual brands like Ate, Trw, or Bosch
Reason i say this is i am yet to own any front disc either than the original that doesn't vibrate upon braking.
Here is an example of the prices to expect:
BMW F10 Sedan 520d Brakes. Read more
euroautoparts.co.za