To be honest, I've had 4.56s and 4.11s in my 8 3/4. Currently have 3.91s. It is just as quick and fast as the two steeper gears. But then I've got a 500 hp 440.
Still, if it were me... I'd put 3.91s in your car. If you stuck a shorter tire it would act just like 4.10/4.11s, and if you do decide on a longer excursion you could use the 30s.
I've got a new set of 28" tall slicks, and if I live long enough to wear them out, I'll probably go to a 9x30 .
(For what its worth, I bought a 4.10 nine inch center for my other car... but I have 30, 31, and 33 inch tires I can use.)
Edit: richmond gears would be my choice.