For the fronts, you can use brake discs from a E38 750iL which are 334x32 and have them machined to 332x30.
The pads are the same as a Mercedes Benz S600, 1993-1999.
See this link of a post a few years back when I rebuilt the front calipers and did some suspension work.
http://www.m5board.com/vbulletin/alp...0-biturbo.html
The rear brakes are the same as the M5.