Valve's Index VR headset is sold out in most regions where it's officially available, and just a few months before Half-Life: Alyx comes out. According to RoadtoVR, which checked its availability across 31 countries, you can only get a unit in Japan at the moment. Even then, you can only buy the headset or the headset with controllers bundle: the full kit with base stations is also sold out in the Asian country. On the headset's official page, the developer notes that it's "busy catching up with the demand" for the device.
Valve has added a "Notify Me" button on its page, and clicking it takes you to portal where you can choose to be notified about the availability of various Index products and bundles.
A spokesperson told RoadtoVR: "We are working hard to build more units and meet the high demand. We are targeting to be back in stock before Half-Life: Alyx ships." The full-length VR entry to the company's first-person shooter franchise is scheduled for release in March 2020. While it will work with other PC-compatible VR headsets, Valve promised that Index owners will get a copy for free.