Walmart offers the Blac Label Small Boys' Twill Cargo Jogger Pants in Midnight or Khaki for $7.50. Choose in-store pickup to dodge the $5.99 shipping fee. That's $5 off list and the lowest price we could find. They come in select sizes from S(4) to L(7).
The planet will thank you, your local (overwhelmed) landfill will thank you. Even your budget will thank you.