If the flywheel is the same as the 540 and I guess it is, Autozone has the torx bit. The torx bolts stay with the flywheel after loosening.
Also remember not to apply loctite when you bolt up. The V8 flywheel bolt holes on the rear flange do not penetrate the flange so there is no concern for oil leak. BMW recommends oiling the bolts before tightening.