You will not find it marketed. Chrysler used that breather cap with the hose "bung" in 1968, part of the "Clean Air" package used Nationally.
In my experience you need to tour a wrecking yard. Or, get yourself a new cap made for an old Chevy small block. It's the same cap or if not Close enough, I use one on my F. Drill a hole on the side and solder a bung to it, paint it and that should do it.
-----Original Message-----
From: "Ronald Klinczar" <rjklinczar@xxxxxxxxx>
Sent: Friday, January 7, 2022 8:19pm
To: "Chrysler 300 Club International" <chrysler-300-club-international@xxxxxxxxxxxxxxxx>
Subject: {Chrysler 300} Oil Breather Unit
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