I'm not located in the UK, but I'm a Feisol dealer (and APUG Sponsor). You can see complete specs and prices on the entire Feisol tripod line at:
I personally use the Feisol CT-3342 (3-section legs, no center column) for backpacking with my 4x5 Toho FC-45X. It will handle your Fuji GA645Zi with ease. It's longer and bulkier than the CT-3441S Traveler Tripod, but as long as you don't need it to fit inside your pack, or inside an airline carry-on, the size shouldn't be a problem. In terms of weight, it's only about an ounce heavier than the more compact CT-3441S, but gives you the other features you desire (3-section legs and no center column).
If you have any questions about the Feisol products, I'd be happy to answer them here, by PM or though email.
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