You have probably found all that exist as aftermarket--None. Tail lights are in the same category.
The BMW variants were the standard ones that you have, Smoked and the French full yellow across the light bar.
Your BMW dealer may be able to get the Smoked for you. (Germany stock) or Gault BMW in upstate New York (Google "Gault BMW" for a parts department phone number and ask for Charlie who is the 8 specialist)
There were only 7000 8 Series imported between 1990 and 1997. At a thousand cars a year aftermarket for us is almost non existent. IIRC they sell more 7 Series cars a month than that 7 year total.