Going to Katmandu for a trek in October-November. I'm tossing whether or not to buy a sleeping bag locally (in New Zealand) before going, although I'm unable to find very warm ones, the warmest 've seen only goes to -15 deg. and I'm told I should get up to -30/-40 - we will be camping every night up to an altitude of over 5000m. I've read that there lots of counterfeit brand bags available there with mediocre quality, etc... Can anyone advise whether I would be able to buy (or rent) a good quality bag in Katmandu (what shop/where) which will keep me warm enough. Tks.