Relativty  – An open-source VR headset
This might be a fun weekend project to work on, but cannot be built for $200. The displays alone (and their driver PCB that accepts DisplayPort) cost $195. They are also not 2K but rather 1440x1440 (or 2.0736M pixels). Maybe the displays were cheaper when they built this. They also hookup a 6-axis tracking chip (MPU-6050) to an Arduino board and feed it to a PC via usb. Even if tracking was working perfectly, this would be a cut down version of an Oculus Go, which additionally has smartphone electronics integrated, can run VirtualDesktop, and can be had for $150 as of this moment.