get the entire rear beam. looking £50 with everything on i would have thought.
the gti/vr6 has built in anti roll bar and having the entire rear beam just makes life easier, as you can bolt yours off and bolt on the new one, and connect up the brake lines and handbrake cables.
not 100% about the mk3 tdi, but i think you may need vr6 handbrake cables. i needed to get gti ones as they are longer to suit the new beam. also not sure if the mk3 tdi is 4 or 5 stud? if its 4 stud and you want to keep it 4 stud, then you are going to need a set of mk2 gti discs.
the brakes are 226mm on the rear. would have thought it a sensible idea to get some 280 brakes at the front too. get some gti/vr6 280mm calipers/carriers and bolt them on. once again, if you want to keep 4 stud you will need new discs, in which case you will need g60 front discs.
im currently doin this upgrade and keeping my car 4 stud btw.