You can find candy tins that are the same diameter of the Nalgene, and an inch tall, in lot of the Big Lots, Christmas Tree Shops, and dollar stores around here. Put your kit in that, put a few wraps of electricians tape around it (say... ten wraps of bright red tape), then wrap it in a bandana so it doesn't clank. Put that under the bottle. Keep stuff like the knife, ferro rod, and the like in the pocket.

You have to replace the tape every six months or so, but electricians tape is cheap.

I will say that while the metal isn't as heavy as what is in the Altoids tin, I find they are just as tough when the force is coming from above and below.

I'm thinking particularly of these, but this price is higher than what I pay:
http://www.amazon.com/Cambridge-Thames-Mixed-Fruit-Drops/dp/B002UTU64O

If you wanted to be really sure of rust resistance, sand it, tape the side partway so you can close it, spray paint it something like nuclear green or hunter orange, put down a layer of clear coat, and you're good.