power window regulators on the cheap

[LH Lead-Foot]

I would like to ask what was used on the center pivot? For this to work, 1 arm needs changed.
I would guess there is a special rivet, one with a shoulder has to be used. This way, it can be peened to hold the arms pivot point in place tightly, yet allowing for proper movement.
If a stepped rivet was used, where did you find it? A bolt with the right size may work but requires a unlock nut installed. I would prefer the rivet approach.

On the farm, rivets where used to hold the blades on the cutting bar of a hay cutter or combine. Maybe, a farm and home would have this hardware.

What say you? Oh great inventor of power windows on the cheap.