N Santiam and McKenzie
Not sure if you are planning to hit the valley (you mentioned coming "up" to OR/WA, but didn't say from where), but if so I second laterwagged on the North Santiam suggestion. It's come up quite a bit in the last week or so, and should be a Class III run right now. BTW, it's pool drop, and the salmon were plentiful last I was there.
I would also check out the McKenzie River if you can. Amazingly scenery, crystal clear water, and nonstop action. Olallie Campground to Paradise Campground is 9 fast miles, and a good continuous Class II with Class III features here and there (careful solo b/c a swim could be lengthy and/or result in lost gear - basically no pools anywhere on this stretch). I shuttled by bike and it's a nice ride; uphill the entire way, but steady and gradual. Hit me up if you're in the area and looking for people to join you.
"This river don't go to Aintry."