I contacted the seller. He was told by the 80 year old owner he is selling it for that it came off a 216 using an early Wayne 12 Port Cylinder Head. He did not know the significance the cylinder head and only listed it by the engine size.
It may be a good buy for a Wayne collector.
That adds up. The posting didn't seem to acknowledge the 12 port significance . . . as if the seller didn't know what was in hand.
regards,
stock49