$25
It's similar to this model, although slightly older (purchased 2017): https://www.rei.com/product/847864/camelbak-mule-nv-hydration-pack-100-fl-oz
Pretty lightly used -- I got a running vest and have always grabbed that instead for day hikes.
One caveat is that it does not come with a hydration sleeve.
Pickup is in EV & venmo-only please!
Please do not message this poster about other commercial services.