You can get the whole connector on ebay, just bought one to replace poor quality one that came with inflator I use for my bike tyres.It is the hand grip for a 'PCL-3' tyre inflator about 4 inches long and 3/8" bore up the spout.
(Mine is perished and about to fall off!)
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Thingybob.
Ain't heard that for years
That's because you can't buy them anymore