Um, has anyone thought about getting one (or more) of those good ol' US Army stainless steel canteens from WWII? The cap is easily removed so that it doesn't suffer fire damage, and there are still a lot of 'em around -- but the prices are beginning to spike. Still, though, they're no more expensive than a modern-day stainless water bottle.
Pair one with a canteen cup, and ya really got something. (I generally carried at least one stainless canteen and two cups.) If ya don't like the canteen rattling in the cup while you're traveling, just slip an old sock over the canteen before inserting into the cup. Voila! Blessed silence
For ease of handling, throw a small pair of water-pump pliers in the bottom of the cover before inserting the canteen cup. (They're not easily found but they're out there, somewhere...) Toss in some of the large, commercial-sized coffee filters and a heavy rubber band, and you've got a field-expedient pre-filtering system to remove the dirt, silt and other solid stuff from the water before boiling it.
PS: Here's what one looks like. Note the horizontal seam that separates top from bottom. Don't get the aluminum ones (seam goes vertical along the sides) because they'll get a dent if you look at 'em too hard.