I used rear calipers from a ‘78 Cadillac Eldorado. They can use your cable e-brake setup. It took me a couple of adjustments until they’d hold okay, but by themselves probably wouldn’t hold the truck on a boat ramp with a boat tugging on it. Honestly, I never really tested them much, but they’d pass a visual inspection. Not sure what they do for states that test parking brakes.
I pulled the cables when I redid some stuff on my truck and haven’t replaced them with new ones yet. Park in my auto holds it fine, but the thought still crosses my mind whenever I park somewhere steep. I have some harbor freight wheel chocks in my tool box if need be.
I see your truck is a k10, but I know for 205 equipped trucks there are cable actuated driveline disc parking brakes. With a SYE on any TC, I’m sure one could be adapted.