Ah James,
We both are sharing the same problem.
My courtesy light looks exactly like yours but is chipped/broken/uggly-looking as well. The original 230SL-courtesy lamps are NLA and the 280 style looks completely different as Mike showed on his pic.
I have collected a couple of originals over the years and none is perfect; they are all chipped, broken, rusty, inside chrome is fading etc. ...
Pete is correct. I once found a VW (old) beetle lens which looks obviously the same - with chrome-plated surround.
However, there was one electrical connection less inside - only two, not three like on our cars.
I guess we have to live with some sort of compromise ...
Best,
Achim
parts & knowledge collector