Hi, I had to piece together my to cars exhaust manifolds to get an acceptable price for them. They don't match, I even had to get the head pipes custom made. I too like the old manifolds, very simplistic, and great heat sinks as well.
I just took a look on Craigslist here in Arizona, someone near Flag Staff has a lot of big block HP manifolds, he want to sell as a lot. I can't see if good or bad, usable or un-usable. I know when your looking for a specific part, it's always on the other side of the country or its just out of your price range. Have faith, you'll find a set that will fit your needs eventually. Good luck
Steve