As I mentioned earlier, you can easily swap the bezel (what you call case) for an all black one, and swap the strap for a black one. Then you will have an all black watch with white hands and indices. That is what I did.
Here is my module from the yellow.watch (white hands and indices), but with a black bezel and strap:
These are the pieces you can swap around: Module, bezel, strap.
Very easy to buy a black bezel and strap to go on ANY 2100 module.
You buy a yellow, gray, or beige GA-B2100 (they all have white hands and hour indices) and just put a black bezel and strap on the module that has the white hands and indices. You can buy bezels and straps for low cost.