However, because of the Chinese New-Year holidays coming up, the leadtime they confirmed is at double to triple their usual delay. What that means in practice for us, whether we order now or at the end of January, the delivery date would be practically the same.
Another colleague of mine also recommended we avoid ordering anything during the rush leading up to the holidays, as the quality of output from China usually drops quite a bit. So what I'm thinking is we wait it out, using this extra time to get more people involved, and order all three types of capsules: CK12, K87, and K47.
The capsules we'll buy are the microphoneparts.com model numbers RK12, RK47 and RK87. The CK12 is definitely used by Telefunken for their AR-51, but for the K87/K47, the only one I can think of is Mojave (someone else might have some other commercial examples of their implementation?).
The factory pricing for each is:
CK12 – $28.80
K47 - $27.50
K87 – $26.50