Eggs are a great choice. I also like to cook up a whole bunch of beef or chicken once a week or so to keep on hand. I'll do something like 5 pounds of ground beef at a time, vacuum pack it and freeze some of it to use over the next few weeks. Just pull it out of the freezer or fridge and add it to a salad or whatever.
Canned tune, salmon and chicken are also solid options if you can't refrigerate. Jerky is my favorite option, but it takes a bit of time to make. Usually I'll use my smoker and do up 5-10 pounds of top round cut across the grain at a time.