>There's a Lochsa in Oregon?
Sweet. I need to check it out. I LOVE the one in Idaho.
Cross the Lochsa off your list if you truly want a high-solitude multiday river. You can camp on it, but it's not really known for camping.
It is an incredible, pristine, III-V (mostly IV- to IV+) with incredible features. It is more of a daytrip river with nearby camping opportunities. It gets a lot of commercial traffic, but it's a really fun scene.
If you and your brothers are all rafters, it would be worth the drive out, camp there, and float 5-6 days. Get there before mid-June.