Quick and dirty prototype Made a med panel insert for a SAW AMMO pouch . Back side has room for small general FAK/BOOBOO KIT
My inspiration for this was the medical insert for the mag pouches.......but it is way too small for my needs. http://www.optactical.com/atslowprmein.html I wanted something that was 7" tall, 6" wide x 2.5" deep so i could carry a GSW/Slash bleeder kit, and a small general FAK while hiking. so i made the panel from an old cracked King Pelican case (part of the side plastic) that i had gotten warranted years ago (they sent me a new one). The grab handle is a piece of truckers round hollow tie down bungee i found on the side of the road. The red cover is dual wall with adhesive 3:1 ratio heat shrink tubing, and the cordage is from 5COL , the Type 9, 2000lB Kevlar .
I like where you're going with this! We are talking with a sewing shop about a similar project that would go in HPG Kit Bags. Attached are the medical insert from the Air Warrior PSGC, and the insert panel from First Spear's MTAP. They're pretty similar in size to your project. The PSGC insert has a zippered pocket on the back that holds a pressure bandage.
Quick update--I talked with Evan about an HPG gear insert while I was at SHOT. He seemed interested in the idea, so I'm waiting to see if he runs with it.