l missed out, had to order one from a cycle store in Colorado!
However, even with VAT, import duty to the U.K. and postage it's come to $147 which is not much more than if l had bought it in the U.K.
The only U.K. seller l found with stock is selling them at £200
Lbs told us yesterday they just put an order in getting them Jan 2022 another order went in last week they will get those October this year unbelievable
The OP's bike came specced with a GX XG1275 cassette, so essentially can run any SRAM XD driver cassette, whether that be 12spd or 11spd (with mech and shifter change)
Yours (@lightning ), has the NX cassette, which means to run 12 spd you're a bit more limited. For SRAM its either the same NX or lower down SX, and I think Sunrace do one
With appropriate mech and shifter changes, you could also run any Shimano 10 or 11 speed setup, along with any other branded HG compatible cassette too.
For what its worth, on my non E fatbike, I'm running an XT 12spd mech and shifter with the same NX cassette as you, and it works without issues.
Well, l did some internet searching today and managed to secure two SRAM GX 12 speed chains, a set of GX jockey pulleys, a NX 12 speed cassette and two Shimano 34t front chain rings.
The parts are out there, well some of them are, but it takes time to find some random bike shop with a clunky website where nobody has emptied their stock of chains/cassettes etc
For instance Cannock Chase Cycle Centre in the U.K. currently has the GX 12 speed chains in stock at £30.
The big stores are quoting November delivery, although there are alternatives for the SRAM chain such as KMC