Ok, as for the part that will be in touch with my face, I used a plastic mask bought from a hobby store. I originally planned to use this in Phantom of the Opera mask, but it does not sit perfectly, and it is a woman's face.. But, then it hit me. This could be used in the Goggles.
Here are some rough sketches for the cutting.
Viewed from the side..
And from the front, before cutting
After a few close moments with my dremel, I am here..