That should have an interesting story behind it! A "barn find" type discovery in a warehouse? A photo search showed an at least one year old photo from the Indy site but these castings haven't been available from Mopar Performance for decades. Casting # is 4772576, an over-the-counter 308 head replacement with no EGR holes. They also had a wide variety of bare, stock-type assemblies, 2.02, 1.88, ported & T/A versions in the catalog. I doubt it's a previously unknown casting number (4772575). I'm surprised Indy hasn't corrected the number. I know several class racers who like this head for 1.88 valves. But it depends on the class and how they planned to modify them.