Here's the twin of a pannier I made last month.
13" high with a 9x6" bottom. Cordura nylon & acrylic-coated polyester.
Put a simple shoulder strap on this one.
Hardware from Jandd.
I changed up the frame pocket on this one. I made it a lot simpler. Now it's just an open pocket with a little lip at the top, sewn onto the bag. The lip is one inch deep, and the frame board is one inch shorter than the depth of the pocket. So you put the board all the way in the pocket and then push it up under the lip. Super simple. You see this design in skateboard wrist guards.
Of course, the frame isn't the full length of the back, but I don't think it's a big deal.
And Velcro to cover the bolts, so they don't scratch up your stuff.