They are still available thru Fel Pro, possibly others like Victor or McCord. Fel Pro doesn't show a manifold set, but does have a head set which includes the manifold gaskets, part # HS 7370 S. Should be a 202 CI engine, you can reference engine model D202, D6202, or DS6202. You should be able to order that part at a local parts store or engine rebuilder, as this was a fairly common engine.