This guy says he has one, or at least that is what he must mean: "Tublular gt-40 upper and lower manifold. Thia is the hard one to find-350 obo" Fairly reasonable price.
http://sfbay.craigslist.org/sby/pts/4933281065.html
http://sfbay.craigslist.org/sby/pts/4933281065.html
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