I found this foam thing at a local store that sells industrial waste materials suitable for art projects. Everything is in bins and piles. The major local industries that seem to donate a lot are the Decker's shoe company and medical device makers, but there are certainly other local industries that donate and I don't think this thing was used for shoes or medical devices.
This foam thing is exactly what I've been hoping to find. If you know what it was from, let me know. Perhaps I could find more if I knew what it was used for originally.
Side view. It's just the right stiffness and thickness.
Here it is compared to the back pad that my Gossamer Gear pack uses.
I cut the edges.
Here it is installed. It's a tad short, but it's not going to fall out. It is comfortable. My hope is better air flow on my back.
