those part numbers look legitish...but if you're going to get anything in the B6 XXX XXXX part range it's going to come either straight from affalterbach, or some one who got it straight from affalterbach. BTW can you post pictures of the sills you have on hand?
It's going to be a long shot trying to get it from a local dealer. If you do find someone who can supply parts in that range, please let us all know.
And for the ultimate prize...if you can get me one of these:
B6 695 3813
I will bow down to you and give you mad props. No it's not expensive...just a bia bia to track down.