So, here we go with the white area inside the "eye".
Looking at pics of the original, it looks like they started with another hemisphere, cut right back and glued onto the clear one. Then the "teeth" of it are strips of another hemisphere glued over that - you can quite clearly see the stepping of them in some shots.
I don't have the financies to attempt such a thing so, instead chose to draw the entire thing onto masking tape i'd covered the clear hemisphere with, draw on the pattern, cut it with my scalpel, remove the areas that won't be clear, spray in White Primer, remove tape and lightly draw the stepping on with a soft pencil.
So this is it, plonked inside the outer "eye".