Robby, I think you’re best off exporting to PDF as a “normal” job type and then asking the print shop to print it as a booklet.
The only other option (as Daniel explained last September) is to temporarily plug your computer into a printer that can handle 11x17. Then that paper size will appear in the right panel of print mode, and with destination set to Print you can then set that paper size, revert destination to Graphics and export your booklet.