Unicomp (http://www.pckeyboard.com/) is a great source for the IBM Model M style keyboards.
Of course, we have private offices. I would not advise using these great keyboards in open floor plan offices or coworking spaces.
To your second point, when it came time to get a mechanical keyboard for a open plan office, I bought a firm, but non-clacky Cherry switch keyboard. I quite like feel of it... there’s something satisfying about the Unicomp / Model M, but I can’t help but think the actual typing experience of the Rosewill generic Cherry keyboard isn’t a bit better.
That says more about having open floor offices than having to restrict personal use of the single most important input device in many offices.