Well - I'll be %$%#%#%!
Dealership got back to me and said despite the listing in the German database it is indeed NLA.
I was a bit over confident. Usually the database is a good indicator. I reckon the number of requests might have woken up the Mercedes spares beast though.
Seeing as this part really and truly is NLA - I see no reason why the following link should not be posted.
These people =>
C&C Parts BV
Are often quite helpful if you can't find brake parts.