Turn the number he read upside down and it is indeed a 452 head.

So there are now THREE 452 heads! There's the original 452 with no mark on the front of the head. Then, the story goes, MOPAR engineers changed the 452 head to have more port wall thickness. That head has a "1" cast onto the front of it and back in the day it was found to be better for porting than a regular 452. The bigblock was already known to be phased out so instead of creating another casting number they used the same one with the extra identifying mark.
Now John has pretty thoroughly described another variant of the 452 and my guess is that they were still selling 440s for motorhomes and ran out of the 213 head or whatever thay had been using, so they made another modification to the 452 casting and gave it "11" marks on the ends to identify it.
I bet your friend's heads have a really late casting date.

R.

PS: To further mess things up, not all 213 heads used peanut plugs or had the extra cooling holes. I have a pair that came off a Newport and they use regular 3/8" gasketed plugs and have no extra holes.