Just want to agree with the park suggestion, I see SAHDs at the park all the time in the middle of the day. Our area has a lot of them, though. But you can also meet other SAH parents in classes, like a family music class, library storytimes, gymboree, things like that where you can bring both girls. Zoos, museums, kids art studios or play cafes, etc etc. Not sure what's in your area, it sounds pretty rural?
My DH and I notice a lot of times conversations between parents get split according to the sexes, so when we get together with my parenting club he always feels left out by the moms. It's hard for a guy to jump in when a couple women are talking, I know. I try to be really inclusive and make sure I strike up conversations with dads the same as moms, because of that. All this is to say...go ahead and be friendly with the moms, too, because if you try everything and can't find any local SAHDs, maybe you'll meet some moms that can be friends to meet up with too for outings. Maybe some of them will "get" it.
Good luck, one of the hard things about being a SAH parent is feeling so isolated and not having much adult conversation, so you have my sympathies!