Would it be practical to EDM this spacer with an order of 25-50 pieces? Material is .500" 316SS. The shoulder isn't needed so they could be wire cut from plate. I'm not real familiar with EDM so I wasn't sure how they are in a small production setting.
If you don't need the flange it's an easy part for the wire EDM.
The OD teeth will need a jig to hold the parts for finish cutting two of the teeth if you need them accurate, but it's not a difficult job.
You could stack plates and cut several at a time.
Remember though, you will have 0.005" radii on all the internal corners, both on the ID and on the OD.
If you can't live with that you can undercut the corners with a shallow 0.010" slot into each corner.
If you can't live with that either, you can't make them on the wire.