Hi Mixie, try Yeomans Outdoors, they have outlets in those areas. Check out their website for contact details; hopefully will have one pitched somewhere convenient. Good luck!
Thanks for the reply Dinkydeb, I've been in touch with them and they're not selling them this year. Have located one on display near Chester but it's a fair trek!
We're keen on this tent too, having seen it at last year as the 500 and just yesterday as the 600, at Camping World in Horsham (too far south for you, I realise). We really like the compactness and quality, but I'd take the 6 berth claim with a pinch of salt. I think the width of the inner is actually narrower than last year's 5 berth, and is also narrower than any other 5 berths from other manufacturers. If it were a foot wider we'd probably have bought one.