I’ve flow in there several times for fly-ins. Great place to fly into. I would suggest you get familiar with mountain flying techniques since that is somewhat difficult terrain around there. Know your density altitude calculations and how to lean. Not sure about camping under wing. There is an FBO there so you can call. Some approach the airport over Lake Wallowa or from the north over Enterprise. There is a tram that takes you into the Eagle Cap wilderness area and of course camping on the Lake itself. Enterprise and Joesph are interesting, especially the bronze factory.