Erector set replacement bush wheel

A neighbor gave our kids a great Erector set, but a few pieces seem to have gotten lost along the way. To build the Ferris Wheel we needed four "bush wheel" parts (officially, "BT Pierced Disc") but could only find three. Hopefully this can stand in as a replacement — I'm intending to 3D print at least a test piece, but this may mill nicely out of an aluminum plate as well.