After leaving it overnight with the problem happening, I tried pushing it in neutral with the engine off - pads on the calipers. Jabbing the pedal didn't change it, pulling the check valve out of the booster, pulling the MC out of the booster - still dragged.

I started it briefly yesterday to reset the booster and today I had a free roll in neutral - after I pressed the pedal (engine off) enough to seat the pads again, they wanted to drag.

Anyone know offhand what vehicles/part numbers would get me a 15"-ish long hose with a 10mm banjo fitting?

My current hoses I got as part of a kit from Dr Diff, but I would rather grab something from a parts house in case I have to do a shrug-n-return. I have looked for a few different 80s GM trucks and cars but they're either too short or have the wrong size frame-end fitting.