I'm using a 100% cotton by cascade-Pima Melange. Lt. worsted. I bought mine from "one Fine Yarn" for $2. 85 (or somewhere in that price range) excellent price! I love the yarn. I hope to buy more soon, before it's all gone.
Let us know what you find--I'm always on the prowl for cotton yarn--it's
all I use. Living in the deep south makes finding an excuse to knit challenging! & finding suitable yarn.