I cant answer your question, but just a quick read tells me you are paying for the quality, knowledge, tooling and manufacturing costs.
You are unlikely to find an “exact match to the original” at a “reasonable” price.
How much is time worth? I tried four GT350 H- pipes at $90 a part, shipping them back and forth, installing and uninstalling them, (each time wasting four days) before I bought a Fuller pipe. That install took ten minutes...
Its good to have choices and I appreciate the fact someone has stepped up to make things correctly. I have bought plenty of off shore crappy parts. Probably more than most people. I have made some parts from time to time as well. You cant do it inexpensively. Almost certainly Mr Fuller has spent hundreds of thousands of dollars on his products. Dont worry we wont tell Mrs. Fuller 😉
How many times have we read, “why doesn’t someone make these correctly?”
How many people actually accepted that challenge?
Just my observations. I am willing to pay a premium for that effort and the quality.