Unfortunately, the supplier that stocks these is the sole-importer for the product currently. There are no Roccat Kave in stock and the ETA that we've been given is for March. It's highly annoying that they haven't restocked, since the product was sold-out in December already.
Would you like me to notify you once they're back in stock with that supplier? From there, you should be able to source the headset from your preferred e-tailer.