Can anyone identify these heads?

They are not J heads. The exhaust ports look 318 size. A 340 head has an intake port height of ~2 1/8''. Heads have been resurfaced. Fresh valve job. Head was cast for an air pump motor as the exhaust flange is different [a mid 70's thing]. Extra holes next to head bolt holes. The casting number doesn't seem right for the head. ------ Sorry, I can't help you -----