The DIY tuning fork clock is very cool. I am hard pressed to understand why accutron doesn't still make and sell tuning-fork watches. I really admire the creative use of resonance frequencies (not dissimilar to quartz watches but cool that you can really see the tuning fork for you watch as opposed to a diminutive quartz crystal).
They have done a re-issue, which Dole has linked to (I'm not going to lie, they do look smashing)
I think the reason why it took so long is a combination of snobbishness (its not "mechanical" enough) and cost of manufacture. I assume that most of the tooling has been lost, and it required a lot of work to re-learn how to make from scratch.
But accutrons wern't that cheap when they launched, so I think they are within 50% of their original price, judging by my half arsed inflation calculations.
The smaller ones look the same but are less beefy.
I used one to make this clock:
https://www.secretbatcave.co.uk/projects/electromechanical-c...
Which instead of using a well disciplined time source, uses a tuning fork and 74xx logic to drive it