If you want to carry fresh eggs, coat them lightly in petroleum jelly (Vaseline?) and store in cardboard-type egg boxes. Invert them weekly to stop the yolk settling and they'll keep in a locker for several weeks even in hot climates. If you're unsure of their freshness check this link for advice http://www.backwoodshome.com/articles/matthews53.html
Also, if you have an oven, learn to bake fresh bread, great for the morale and lovely to eat. And keep powdered milk (Nespray), much better than the so-called long life cartons of allegedly fresh milk. I once had a dozen of these turn in one day with widely varying sell-by dates. A few burst and contaminated the entire locker.