Dear Don;
The Wayne Mfg Co. was re-created in Pentaluma, Ca. a few years back.
It started making the heads again & then stopped as fast as it began.
There many rumors as to why this occured, but the "general" thought is that there were 3 people involved in the Mfg process and they had different views on how to proceed etc.
When (if ever) they will return is anyones guess today.
Happy trails.
PS: The one I bought from Harry in 1962 (off his Roadster) for my 278, had a semi-round chamber.