I made my own based on this this video and other ones linked in his youtube account:
https://www.youtube.com/watch?v=6wjXPJyNq5sI made additional modifications due to my MCS. Painted with shellac and afm hardseal to seal in plywood and wood smells. Also made a vent with a battery powered usb fan (80mm) that goes into my austin air purifier. I used magnets attached with silicon to the pvc pipe at the end of a vaccum hose to attach it to the air purifier in a way that can easily be moved thanks to the magnets.
Pictures below:
