>TL;DR: I’m getting frustrated with the general scarcity of MK related stuff and made up prices. How do you cope?

Having built over a dozen keebs, I have coped by:

1. building with the many boards, switches, keycaps that are in stock (Alexotos' vendor list is your friend in this regard)
2. selectively buying out of stock items on r/mechmarket
3. selectively joining GBs and being patient
4. choosing to not care about unobtanium things

It's not that different than any niche hobby where there's a range of mass-produced, small-volume, and boutique/artisan items available.