Add WMPU DEV to another WP installation on site

I have your premium services on my main webpages of intelli.tours. However, my e-commerce area is on a separate WordPress installation on the same domain. It is Intelli.tour/reserve. I had to do to this becase I needed a different theme with different functionality for my e-commerce end. How can I add all the service I have on the main installation of intelli.tours to also be on intelli.tours/reserve? What will the additional cost be?
Thanks!
Jeffrey Kirkman