no, the mainframes hardware is not consumer level. Go search IBM for mainframes for instance. I think the cheapest mainframe would go for 20-40k at minimal. They mostly go for around 2 million etc. They are made up of parallel processors, the hardware is most likly unqiue for each machine.
You are thinking of consumer level PC processors. Thats the reason these jobs are so scarce, because the people who used to work on these mainframes are retiring and now they dont have any skilled people. They are basically two different universes, totally different.