I would say any blade you like if well treated will do fine. Perhaps a Wapi just due to the durable scales, they were made for packing after all. A big help would be one of Tonys vegan strops because they can be rolled up and take dampness with no ill effects. I would also carry a barbers hone if you spend that much time in the bush you might find time for honing or you may need to refresh your blade while "out there".

If weight is a concern, I would look at the Shavette or other open holders of disposable blades. This is what I will be bringing in on my next packing trip. The razor and a five pack of blades would weigh just ounces and take up little more room than a pen while keeping me shaving daily for up to ten weeks. It isn't as much fun as shaving with a real straight but gives you all the convenience you are looking for in a light small durable package.