hey mate,
I think Sirui make some awesome tripods. I'm a big fan of their N-3203x tripod. They also have a dedicated travel range.
That being said, both my tripods are Induro CLT 403's which I really enjoy using. Both are carbon fibre with a centre column and have excellent build quality. My tripod heads are all Sirui (VA-5's and VH-10's).
I went Induro for the Tripods because of the price saving in Australia over the Sirui tripods. I managed to pick up the Sirui heads for a very good price on Ebay.
The thing to remember about tripods is that the simpler is better in terms of stability. A 3 section tripod is going to be more stable than a 4 section tripod as the 4 section tripod has more joints and therefore more points to flex at, but the 4 section tripod will likely pack smaller.
a tripod with a flat base is going to be more stable than a tripod with the base plate mounted on a centre column. You'll get less stability again once you start extending the centre column.
I regularly backpack my Induro CLT 403 with either my Swaro ATS 80 or Zeiss Diascope 85mm. I carry everything in an Eberlestock Halftrack backpack find the weight to be inconsequential when I'm doing bushwalks and treks.
The Induro is well beyond your weight requirements (weighs 2.2kgs/4.5lbs) however the Sirui VA-5 is a fluid pan/tilt head that weighs around 600g. I find my that both my 80mm and 85mm scopes balance well on this head. Its capacity is 6lbs with adjustable drag on the tilt function.
http://i12.photobucket.com/albums/a227/jeelanamin/Optics/Sirui VA-5 Head/_DSC0156_zpsysu37a6p.jpg
For the tripod my suggestion would be a Sirui T-1204X which is around 2.1lbs
whatever you decide, good luck with your purchase and if you get the opportunity take your scope / bag into the store and try packing the tripod and mounting the scope.
cheers
Jeelan