I'd prefer to buy a tripod- monopod combination, where one of the legs dis-assemble to form the monopod.
the carbon fiber sirui n-2204 extends to 65 inches and collapses to 18 and weighs less than 3 lbs and has retractable metal spikes ... it also has a detachable monopod leg ... $405
you could also consider its aluminum cousin the n-2004 which weighs a little over 3 lbs with the exact same specifications ... $185
a demonstration video of the n-2204
try bhphoto.com for a good price ... hope this helps ...