I have a set of “standard”(original style, raised std port) stage 6’s here that have that casting number.
The “part number” for them is P4529335.
Not including the Chapman stage 6’s, there are 4 different versions of the stage 6.
-Original stage 6(raised std port, straight plugs)
-MW stage 6 with angled plugs(raised MW port, small kidney shaped chamber, needs .485 offset intake rocker)
-MW stage 6 with straight plugs(MW raised port, std heart shaped chamber, straight plugs, .485 offset intaker rocker)
-street stage 6(later called the aluminum commando head, non-raised std intake ports, straight plug)
I've done several sets of the Stage VI MW angle plug heads. They are a giant PITA to make work, but they can make power.
They suck to port for sure.
