Do you do anything in particular in your preps with respect to your vision?
I think back to many movies where someone loses of breaks their glasses. Like in The Mummy where the guy is practically blind without his glasses and his gets stepped on.
My vision isn't that bad. My right (dominant) eye is "ok" for distance, but my astigmatism makes reading street signs a challenge. My left eye is worse. I've worn contacts since I was in college and I've never shot without my contacts. I now have glasses that are more "shooter friendly", but haven't shot with them on.
I've sparred and my contacts have come out many times. Of course at that range, can still spar, but their face can be blurry.

My buddy in HS would surf without his glasses. He said he just paddles after shadows of the wave.
I don't stock up on contacts. In fact, sometimes I put off buying new pairs as long as I can. I have many older pairs of glasses, but I don't think they'd work well for shooting. I have a newer set of prescription Oakleys (was pretty cheap with my insurance), but there are many others that I wanted to try.