Amazon has 24 pack Zebra Pen Z-Grip Retractable Ballpoint Pen, Medium Point, 1.0mm, Black Ink for $5.40. Shipping is free for Prime members or while Subscribe and Save is available.
https://www.amazon.com/Zebra-Pen-…B001BZ6ZN4
Alternatively, it is available at Walmart. Choose free ship to store, otherwise shipping is free on orders $35+.
https://www.walmart.com/ip/Zebra-…t/32538957