Hi,
I just checked my surplus door pile, I have one solid door that is 7 3/4" x 29" cutout and overall 8 1/2" x 29 3/4".
I also have a louvered door I mis-ordered that is 9 1/4" x 33 1/8" cutout and 10 1/8" x 34 1/8" overall, but it has the louvers running across the short dimension so they would be vertical in your installation.
Kevin