The leather ought to hold up just fine--I've gotten mine damp plenty of times and while it's best to avoid getting them wet it's not going to kill them. I don't mean to make it sound like the name is the reason why I'm suggesting it, but you might try the
Condor Swamp Master might be a good choice for you. It's the smaller version of the Viking, which is a personal favorite of mine (though that one would be a little big for your purposes!) It has a lot of chopping power for hard or dead wood while remaining pretty easy to carry or pack, and it's relatively light. The partially sharpened back edge is fantastic for hooking cuts on green vegetation, wood plants, or grasses. The fact that it's stainless is just a bonus. Normally I don't trust stainless machetes as far as I can throw them, but Condor has proven to me time and time again that they know how to make it work.
Your Tramontina should do well for you, too, or the above-mentioned Eco Survivor (formerly called the Eco Lite.) Great handle ergos on that one.
You can't find any because they aren't out just yet. Last I heard was April.