Tom. I may have an unused set of gaskets from the 60s. On holiday until the weekend. Will look then look in the gasket box. They will contain asbestos. Allan
Back from holiday. I have found 4 twin port outer gaskets, but only one centre rectangular gasket so ok for your needs. Will contact you off line with photo. Allan
Looking ahead to a head swap, I found I had no spare manifold and only one head gasket. I have had new gaskets made in modern materials that should be more reliable than very old copper & asbestos ones. Time & trial will tell.