The one I had was a fluke. I actually talked to John Vermersh who at the time was the head of the Ford Motorsports program and he said that they were never commissioned by him.
He said that it was a "cheater". One that was made for a competitive racing team to look stock on the outside but was altered on the inside.
He said he thought that there was probably more then one made but exactly how many was just speculation.
Just the "regular" A331 "Torker" is not a common item. The last one I had I sold for $850. I didn't twist the buyers arm. He kept putting money in my hand until I said ok.
If you can't find one then I'd suggest that you find a regular Ford aluminum intake and take it to an induction specialist and have him match the ports to the heads. That isn't going to be cheap.