Create the pages that need to be single-sided with a blank even numbered page following each odd-numbered 'live' page. When you create the PDF, you can send it out, and it will print the way you want.... but if the folks who receive it will read it on screen, this is NOT a good solution, the blank pages will confuse them. If everyone has access to printers that default to double-sided, then this idea could work. Make two versions, put them on an intranet page,and send an email with links to both versions - one for viewing, the other for printing.
Fred Wagner