Meyle are an OEM quality supplier to BMW for brake discs. This link is NOT, I repeat NOT the ones you need, but as you can see you can pick up all the parts for a maximum of £200.
http://www.ebay.co.uk/itm/BMW-E46-330-Ci-330D-FRONT-REAR-MEYLE-GERMANY-PLATINUM-DISCS-MINTEX-BRAKE-PADS-/150706258717?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2316cb031d
Mintex pads sometimes squeal a bit, but have this combo, abiet I have upgraded E46 325mm rotors on the front of mine I otherwise have no complaints.
You'll find the brake shoes should have hardly any wear - well that's what my indy said @ 50k miles so he just cleaned & refitted the old ones. If you can get to Dartford & leave the car, I'll give u the name of my Indy