Steering Coupler Rebuild "How To"

100% agree, which is why I'm consulting the group who has expertise from doing it in the past.
I'm starting to think that the only good solution is to buy an aftermarket coupler for safety's sake if I can't purchase the correct rebuild kit and parts.

You're in a similar boat I was in. My 66 Dart had the same coupler you're deadling with. Luckily, mine had the two rectangular springs and they were in good shape - as were the shoes and coupler body. I simply replaced the seal and installed a set screw to act as the small safety pin on later couplers.

Maybe try placing a wanted add for those two springs. Are the two shoes and body in decent shape?