coin style headspace gauges

[WWGunslinger]

Does anyone make coin style headspace gauges anymore? Specifically looking for .303 british.
Searching online I found posts referring to Yankee Engineering and Okie Gauges, but both seem to be out of business (Yankee website no longer works, Okie site works, but no options to order, email to them is returned as failed).
I did find one called Firewerks but they only had a gauge for 7.62x54R.

I liked the idea of the coin type as you didn't have to remove the extractor to use them. These would be good to use at gunshows or somewhere you couldn't remove the extractor.
Unless someone makes a new kind that doesn't need to remove the extractor?

[USMC3531]

I had a machinist friend make some for me a few years ago, just washers surface ground to proper thickness