That looks just like what I might need for my 6 inch Verito. I assume that one uses a lens cap for the exposure and you have to put the mirror up after focusing?
The depth from the lensboard face to the bottom is ~30mm, the front dia is ~75mm, and the rear is ~50mm. Think the Verito will fit? If the lens does not protrude into the body at infinity, there's no need to put the mirror up.