One thing you will see from all of the Night-Night threads is that it is an extremely subjective method and there are no guarantees that what works for one person will work for another. Both individual anatomical differences and differing techniques all have an influence. That being said, there was a diagram in the PPH ('Korean Method' chapter) showing a modified torniquet designed to apply pressure in exactly the correct spots, so if you were going to 3D-print anything, something like it might be a good place to start. I also vaguely recall seeing a CAD rendering somewhere else of a similar device, but don't remember where. A forum search might help.
