The Fatshark goggles have a little slot where a lens can go... and you can buy sets of lenses, then a slider in the front of the goggles (one per eye) lets you fine-tune your view.
What I did was take an old prescription pair of glasses from my old glasses drawer, and use the Dremel grinder to cut them to a size that fits into the Fatsharks' ocular slots.
fpv-plastics.com sells ski goggles pre-configured for various goggles.
Modifying myvu glasses to remove the blue screen.