Even if they exact visual replicas, you need to consider a shit ton of other things:
material? chances are 2000 dollar headers are made from 321SS, this is 1000 dollars in material. No replica header that you will get for the cost of shipping will be made of 321.
welds? You can make a weld look really pretty and still hold like shit. It may also be shit on the inside of the pipe, was it backpurged?
just because it fits doesn’t mean it’s good. Let me direct you to my turbo manifold that “fit” on my 240
