How about using a wide mouth 32 oz Nalgne bottle for the kit storage?

You can fit a lot of kit in one these bottles which can be carried in your back pack or attached to the outside on a lashing strap etc. Since you always need water, carry a SS bottle that can be used for boiling the water if needed.
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Earth and sky, woods and fields, lakes and rivers, the mountain and the sea, are excellent schoolmasters, and teach some of us more than we can ever learn from books.

John Lubbock