One of my throttle linkage rod ends was broke/worn enough that it occasionally popped off while driving, not much fun in traffic.  Saw this thread that talked about salvaging the old plastic ones to create new linkages, but did this instead.

Bought some 8mm-M5 ball sockets from Grainger and M5 threaded rod.  I've seen them or similar on Amazon also, but wanted to see them before buying.  Sockets have a wire lock pin, which definitely lock them onto the ball, but they are also pretty tight without the wire.   I wish I had a lathe to remove the unused threads, so I used some shrink tubing to cover them up.

Not factory looking, but works great if you're not into the originality thing, or just need time to round up some unobtainium originals.

Heat shrink is a great idea, might have to borrow that.

Ditto on the heat shrink. Those ball sockets worked great. I had used a stainless steel rod and cut threading on the ends but blacking out the rod looks great.