THank you for the quick response
I have checked Ebay for both parts, and so far, nothing for the w123 chassis. I have seen a few for the w124 though, and one for what looked like a euro w123, but it was a bit different than mine though... (mine is a US spec)
All the parts sites have the tail light assembly, but no trim piece listed. I might also try hitting local junk yards.
Send me a PM if you find that part, and if you are willing to sell it, price, shipping, etc, etc, etc....
Its great to know I can find info I need on this forum!!!