Most cabinet companies will be able to do reduced depth cabinets, and 9" is on a three inch increment, so it should be pretty easy. Keep in mind that a dinner plate won't fit :)

Excellent. Thank you.
I want to mount them on a hallway wall and use them as a bookcase which would allow me a counter to display pottery.

Thanks again!

Why not check out a bookcase (an unfinished wood company can make it without a base, and you could mount it to the wall). That would avoid the upcharge (I think around 25%) for the decrease in depth for a semi-custom kitchen cabinet, plus the upcharge for the inside to match (also not standard). Just a thought :)