Assuming that you restarted your page numbering at the beginning of Chapter 9 and that you have five actual Word pages that are being treated as your ten folio pages:

So each sheet has a single footer stretching across the 17 inches.
You want the footer on the left (bound) part to have the odd page and on the fly-out to have the even page number..

Odd page part of footer:
FP: 9-{ = { PAGE } * 2 - 1 }

Even page part of footer:
FP: 9-{ = { PAGE } * 2 }

I've attached a document with those field codes. Note that as far as Word is concerned, in the Table of Contents and other reference pages these will be pages 1-5.

Attached Files

Folio Pagination.docx (48.7 KB, 8 views)