Fastener Source- Sleeve/Bobbin?

[KTL]

Anybody have an idea where I could source the brake rotor "bobbin" in the attached picture?

I've tried for a few days now and can't find an exact copy of this stupid little flanged sleeve.

1/4" inside diameter, 5/16" outside diameter, 1/2" overall length, etc. as shown on this dimensioned drawing



I've tried sleeve bearings, sleeve washers, shoulder washers, bobbin, unthreaded bobbin, all sorts of searches and no luck.

Calling it a bobbin is a bit of a stretch since the brake application floats by expansion, which is different than a traditional bobbin allowing the rotor to float back & forth on the hat/bell

Thanks,
Kevin