Brembo calipers from a 996 non-Turbo or a 986 Boxster S or Cayman S. Porsche has many Brembo calipers from different cars (in several different colours) so it's best to verify by P/N.
Part Numbers:
996.351.425 (driver side front)
996.351.426 (passenger side front)
996.352.421 (driver side rear)
996.352.422 (passenger side rear)
Additionally you'll need adapter brackets for the front and rear and brake lines. Rally Road offers all of this.
You'll also need to machine 5.5mm off of the base of the front calipers to fit the Z4M/CSL rotors.
As for pads, you would use the Porsche pads for these calipers, but for the rears you will have a rust ring as it doesn't have full coverage of the rotor so I believe some adapters allow for a 986 Boxster/Cayman non-S front pad to be used that remedies this.
I bought a set of calipers a couple years ago but haven't gotten around to refinishing or mounting them yet. A few users have this setup (some local to us).