The Vufine+ [1] is about the best option I’ve found so far. It works and is a standard HDMI display but it’s really small in your vision (so need v large font sizes), has quite a lot kind of obstructive stuff from the casing etc. in your field of view, and feels bulkier than it needs to be.

I’d be happy with much lower resolution like these displays specially if it appeared larger and clearer. I actually bought a transparent OLED thing [2] recently with the intent of trying to hack it into something wearable but no progress on that yet and not sure if it’ll actually even be readable.

[1] https://store.vufine.com/

[2] https://a.aliexpress.com/_BSV8F6

Maybe this would be a place to start.