OK, so here's my shopping list and plan for my back pack. My exciting new project in my quest for a Mandalorian suit.
First, I give you the plan:

Now, the PVC sizes are approximate and may change as I start the build. But this is what I have planned to start. The additions will most likely be sintra strips. But like everyone knows, plans can and may change.
Secondly, I have plans to make the back pack semi working. The plan is to incorporate a fan into the back pack and have it blow cool air into the helmet using #1. Also, if you notice above #8, there is another small box as well as another hose. (Sorry, didn't have a # added to this one.) The plan for that one is to have it be the power for the voice box. That is, if I have one. But it will open so I can add it at a later date if need be. Also, if you look at the picture below, you'll see what looks like a speaker box. If I make the armor similar to the McQuarrie Concept Fett, I may use this as the speaker.

The rest of the back pack will be mainly cosmetic and aesthetic. Though it is possible I may decide to also incorporate a water bladder into it as well. (Just thought of that as I was typing this.)

So, that's where I'm at. Still at the planning, but moving ever forward. Input would be appreciated if someone feels the need.