ski wax for touring is based on snow temperature; softer for "warmer"; harder for colder. The proper wax give you the shove when skiing. This kind of waxing is not necessary if the skis are just being pulled.
Your best bet is to get what they call a "base" wax that goes on first and just stay with the base layer. They usually spread it with an old iron (don't try this with wife's!) and put on several layers. Probably difficult to do if the skies are not easy to get at. Anyway, get the hardest wax you can find and it should last the best. Most ski shops will carry the base wax and give you advice too. You can even use paraffin in a pinch but it will wear off pretty fast.
I have two tours in Alaska and even commanded an infantry battalion up there. The older wooden Army skies (White Rockets) are not as bad as everyone claims, but the older ones can get brittle and snap if not treated with care.
