3M Multi Gas Vapor Cartridge, 60926, $13.83 @Amazon

https://www.amazon.com/dp/B009POHLRC/
3M Multi Gas Vapor Cartridge
Filter number 60926
P100 Respirator
$13.83 @Amazon
One Pair
Ships and sold by amazon.
Free shipping if you have prime..
This is the cheapest I have even seen them.. Usually $18-25
CamelCamelCamel is showing this as the cheapest as well.
For many people these are overkill, but hey, you only get one set of lungs..