Real, no bullshit, prices from slightly out-of-date Europractice access to GlobalFoundries 22nm process:
50 prototype dies, unpackaged, untested
48,000EUR for up to 3mm2 plus 16,000EUR per each additional mm2.
I'm not up to speed, but by my understanding is that access through MOSIS (sidehack is based in the USA) is both slightly cheaper and has somewhat more frequent shuttle runs.
A young, personable individual could do the tape out for free by pretending to audition some EE courses in some local (US or EU) school that has the required CAD/toolchain available in the student's labs. I remember from my student days several groups of people that manufactured prototypes on the side while taking courses. The only time my school objected/prosecuted was when some lamers actually physically took the test equipment out of the lab (in effect stealing). Many people overbooked the computer lab time in ridiculous amounts to run side consulting jobs.
Good luck to you, sidehack, personally.