Warning: If you are not competent or do not feel comfortable doing any of these modifications or procedures, then please do not do so. I will not be held responsible for any damages caused by a result of your actions. Now on to the fun stuff!

I picked these up from Circle BMW on the east coast. They shipped me them in about 2 weeks (they had to order them).
I did not install them, but installation is very simple. Just pull off the old molding and replace it with the new one basically. You may want to invest in new rubber boots to fit on the connectors as a lot of times they get torn off when removing the old molding.

Here are a few not so great pictures in the garage (hey it was raining out!)

Update [02.28.03]: Here are a few pictures of the passenger side rear molding's clips and back side. Two of the clips got broken some how so I removed it to replace them.

A few part numbers: (note: these may only be m-technic parts)
small white piece on the left side: 51 71 1 929 320
green grommet for above: 51 71 1 932 996
white clamp: 51 13 2 251 394
white rubber grommet for above: 51 13 2 251 394