I was just down looking at my heads and pulled some numbers off of em:

They're rectangular port cast iron BBC.

14096188

And some of the other ones where m028 up by one of the springs and 188 on the bottom of one of the ports.

I want to sell them and I'm gathering info too see what they are worth.

14096188...70-71...rectangle port...OPEN chamber...454 service replacement, also used on later Mark IV LS-6, LS-7 and 454 HO crate motors, 116cc chamber

From Mortec

Thanks!