A piece of 1 1/4" round wood curtain rod, bedlinered. Drilling the holes for the pins was tough without a drillpress. Actually, only the back holes line up and are pinned. The front ones have pointed setscrews pinching the pump arm. But it was solid and stable with just the one pin. A little leather bumper tucked into the slot on the arm made it MUCH quieter than all that plastic slapping around.
I think we're all Bozos on this bus.