There is a little lake atop the Steens mountains called Wild horse lake. The road doesn't open up til the 4th of july though. Once at the top of the mountain it is a little over a mile hike down to the lake. It is absolutely amazing scenery and the fishing isn't bad either. The average fish was around 12-14 inches for me.
There's a lake somewhere around John Day that has Lahontan Cutthroat in it. I can't remember the name though. Here's a few LC I caught a few years ago up at Lake Lenore in Eastern Washington.