The bashing your TRP or Box derailleur on a rock in New Zealand had me chuckling. As being from NZ, the irony is you could actually get the spares for it here. Other irony is, if it was mid-to-upper tier Shimano you might be outta luck. I had to wait 3 months for a Zee rear derailleur, and that was well before anything Covid-19. Then again the Shimano NZ is run by people who still think an MTB is just a BMX with gears therefore not important, and hardcore road cyclists.
Commencal have done it the interesting way for their 2021 bikes. Some (example Meta TR), are full Shimano and Fox, others are full Sram with Rock Shox.
Also see Microshift for their new wide range groupset. Reviews I've seen and read are pretty good. Kinda inclined to give their 10 speed wide range a go on a 1989 Rockhopper (insert lol comment).