Your cable ends with a knarp. The brake lever grabs that knarp. The other end of the brake lever pivots on the lightly-toothed tip of the "brake axle," which goes inside your hub and spreads your brake pads.
Hobbit cables, levers, "brake axles" and brake pads are interchangeable between NC50/NA50 and PA50.
The hub covers and speedo drives are different between them, though.
I figured this out by taking them apart and looking at it. I recommend you do the same. If it doesn't function perfectly, then make it work.