people in all sorts of hobbies struggling the same way. 5-10,000 investment to make single press dies, stampers want a minimum run how ya gonna sell 200 peices? to whom? a 20 ton stamping press isnt a backyard item, and even 100 year old models are still working. to make small parts you need an inline multi purpose die, and those are insanely expensive.
I need a seat pan for my 67 Cobra. they dont exist. stupid design, center fabric wasnt waterproof, they all rotted. you cant find one anywhere, and the market is too small to warrant a new run.
i would love a new tank for my airflow, but jesus who would buy the bike after i put all that money into it. What i would consider having made if anything, as was stated would be universal copies of accessories.
Many straight bar frames have somewhat the same size opening, I am sure a universal tank could be made that looks good, and would fit many types of bike