I just picked up a Williams Tennessee in really nice shape for the age. Ready for a cleaning, adjustment, & rubbers and it should play. The game is complete except for what I guess you'd call a ball load rod? There should be another rod below the plunger that is pressed to kick a ball over to the plunger. The mechanism itself is attached to the underside of the playfield.

Anyhow this rod and knob is missing. Any ideas first on what this is called and any pictures of what I may be missing? Any idea where to source such a piece?