I'm afraid it's only ever going to be available in A4, but you might get away with it if you change the magnification setting when printing to something lower than 100%. Maybe something like 94%
So far I have found setting the page to US Legal size, then trimming it down to size works. Unfortunately I won't be able to print those pages as a booklet without using a binding machine. Also, I have to make sure the copy is at least 100, because if it's too small it will give me a headache.
