Vent control assembly nutsert thingies

[SeriesShorty]

I finally got my new vent control knobs, but now I can't find the large nutserts that mount on the dash to screw on the control assembly. I must have lost them when I moved.

I didn't see any for sale here, does anyone know where to get them? Or any other sort of replacement/fix/jury rig?

Thanks!
J