Excellent info, once again and getting to what I was figuring. I am a relatively young Pantera owner being born 6 years after my 74 and am not as knowledgeable about the Motorsport heads. I did however grow up in a family that dealt mostly with FE's and chasing expensive 427 parts and now (even before the Cleveland) the modern aftermarket has came around producing great products with modern technology for those too. The question that often comes up then is do you pay a premium for vintage parts such as medium riser heads, when the majority of cars you are dealing with such as Mustangs never had a factory 427 anyways? Or do you buy a modern Survival Motorsport, Edel, Blue Thunder etc...? I know many will pay more to have a Ford oval stamped on parts (I know I often do). I believe that some of these things will be coming up when dealing with 351C vintage performance parts such as listed. Like you said many of the Australian heads are similar or at least comparable in performance and price wise possibly cheaper (or not depending). Lastly with more promises of a modern Cleveland block coming into production paying for a vintage block and then having to get it checked out may not make sense either.
Regardless of all this though I still think there will be many that take pride in chasing and acquiring vintage parts especially with a Ford oval stamped on it. I will go as far to say imo that with the recent increase in value of our cars (especially stock ones) that Ford parts regardless if they are over the counter performance parts or not will hold value more than other aftermarket parts.
