Yugster offers the Foster Grant MicroVision Folding Reading Glasses 2-Pack for $9.97 with free shipping. That's the lowest price we could find for this quantity by $30. They include USA flag cases and are available in +1.50, +2.00, and +2.50 diopters.
The planet will thank you, your local (overwhelmed) landfill will thank you. Even your budget will thank you.