Bet I could impress you with my "moon"
negative
I actually use B&W camera film, folded over three times or so. Once you pull the film out of the canister it's exposed and junk but is opaque enough to allow viewing of the sun if folded over at least a couple times.
It's about the same price as the glasses and can be found at places like Walgreens and CVS
You really could make this, you know
Trans Woman from Austin, Texas