I bought a new pitman arm from Bratton's last October, part 5570, for $41.65. Works great. Don't forget wear can occur not only on the ball, but if the sector attachment bolt works the slightest bit loose or the sector shaft square isn't square and allows any movement, the pitman arm square hole will get worn as well.
There were supply chain problems last Fall, back then new 2 tooth sector shafts were not available anywhere.