Your cheapest option is a welding #5 visor from NAPA for $6 or your local welding supply place for $6-$8.
There is zero need to buy anyone's expensive pre cut visor when you can do it easy yourself.
My install in my Target helmet.
I used Chicago screws with the screw part epoxied to the helmet, modified picture hangers, and nuts to hold everything together. I got to find some 8/32 thumb nuts to fit the screws instead of the nuts as it will make visor removal much easier.
No glue, no fuss no muss easy visor removal.
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Lynn