I'll let Dwight be the final word, but it was available on any Barracuda (not Gran Coupe or 'Cuda) with any engine from 198 up to 383.

Totally non functional option, but cool dress up item!...I thought there was an interest in reproing this option discussed quite some time ago, either here, or perhaps it was at Cuda/Chall.com?, did anything ever come of it?...IIRC these scoops are a potmetal casting that are covered in elastromeric rubber coating much like the E body rubber bumpers?...yes/no?

That was me (Scott) on the scoop project, I still have the molds, only sold a couple sets, demand is low to non existent. Yes, steel cores with a rubber coating (that delaminated from the core quite easily) it was not the same material as the bumpers, softer durometer. Also, there were two styles made, probably a running design change. One style had hidden mounting studs molded in, the other style used screws to mount them on that were visible after installation. The repros I made were solid Urethane simply because of the quantities and economics in making such small numbers of them.

Here's a fender tag for a BH23N0 M46 car