As an 'I second this' reply, they look exactly like my old Shankle headers, down to the finish (what's left of it, at the flanges). I had good luck with mine, mounting stayed tight, performance/effeciency, etc. The Alfetta coupe they
were on died a violent death, sadly, a hit and run in front of Patrick's bar in Louisville, KY. My brother has them now (see the 'MadMax' alfetta thread), so they're still in the mix.
I thought they had the flanges originally, but I could be wrong. Have to call the new owner. I bought mine new, from Shankle, so I am sure of the source. It seems like they were $200-250 at the time. It's been a long time.
Sorry, I'm rambling; the point is, I am 90% sure they're Shankles.
. Not looking to dis anyone else's thoughts on the subject.