I don't remember if they are adaptable, but the ones I've looked at or used were sure heavy to haul around vs others.
If this is for a spotting scope, binos, and camera, it seems like the one that Tha Dick posted the link to above fits the bill, unless you want to spend more and have a little more weight for extra stability. But then you can always hang more weight on the lighter weight tripod if you need it. Heck, the your boots alone are probably good for 5-6 lbs... or bring a canvas/nylon bag to fill with dirt or rocks.
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