You asked what to look for in buying snowshoes.
First thing I'd look for if I were in your situation is a source from which to rent or borrow a pair.
As mentioned in a few posts above: they are expensive and if it's a first or only time to use them, don't buy.
Consider the type of snow and terrain you'll be on and your own weight and height and the weight of your gear.
If you'll be in deep, light and fluffy snow, if you are heavyset and if you're carrying a large amount of gear, you'll want something more in the lines of traditional snowshoes.
https://www.snowshoemag.com/2012/11/25/the-morphology-of-snowshoes/
If you'll be in icy conditions, in dense cover or steep terrain, or on groomed trails then modern aluminum and plastic shoes might be best as they have integral crampons.
If choosing wooden framed shoes, examine the wood carefully to ensure there are no knots and that the grain does not run out. They'll likely be made of ash or spruce. Check the points where the seams are lashed to ensure that there's adequate lacing beyond the ends of the joint. For the lacing, babich is traditional. You'll likely be unable to determine whether it's deer, moose, cow or whatever. Just ensure that the lacing is well shellacked, not too brittle and that it doesn't appear to have any laces cut too thinly. Bindings are more variable on traditional shoes than on modern ones. I preferred buckled leather bindings as I could adjust them for whatever boot I happed to be wearing. If you use bicycle tire inner tubes or lamp wick, then you're somewhat set to a certain size boot. Speaking of which, ensure your show shoes have a large enough toe hole to accommodate your boot or conversely that your boot toes fit the hole.
For modern aluminum snow shoes, check the temperature rating for them as the plastic may get brittle. You want the plastic to be more "rubbery". Most are made with some sort of PVC but some are nylon. Check the size of the rivets and look for pairs that have washers under the rivets to spread out the stress. Most modern versions have integral crampons. The binding and toe hoes are somewhat fixed so as with the traditionals, make sure your boots fit the bindings.
Boots. They have to be warm. They need to be flexible but have to protect your arches. You have to be able to wear multiple pairs of socks and still be able to wiggle your toes. I recommend something up to just below your knees. Blisters are less likely when snowshoeing than when walking but the if they form they'll be on the back of your heal, under the arch behind your big toe and most likely on the top of your foot behind your big toe (ouch!).
Sigh, almost done.
As for military surplus snow shoes. Canadian Army snow shoes can be had on e-bay for about $50 Canadian. They are large and light and very durable. I remember our instructor telling us that they were made from magnesium and wire from decommissioned aircraft. I'm pretty sure that was just barracks room rumour, but I do know that they were very good pieces of kit.
For what it's worth, I know most militaries use skis, but the Canadian Army uses snow shoes if on foot. Mostly though, they use snow machines or snowmobiles.
