British made Sleeping Bags, sleeping mats, tents and other camping and outdoor gear (listed as usual in no particular order).
http://www.buffalosystems.co.uk – Great sleeping bags from Buffalo Systems – made in Sheffield, England. Buffalo make fabulous outdoor kit for men and women. Everything is made at their factory in Sheffield, England. Outdoor clothing and sleeping bags. Buffalo products mostly have a Pertex outer and pile linings. Everything they make is simply fantastic.
http://www.snugpak.com – Snugpak do a range of great sleeping bags – take care to choose the manufactured in the United Kingdom ones though. They also do great UK made cloths (just some jackets, trousers and hats are made in the UK), so likewise with their clothing take care to choose made in the UK. Items that are UK made are clearly labelled as so on their website. You can even filter to just UK made products. Only some clothes, some sleeping bags, some bivvi bags, some sleeping bag accessories, some hammock blankets, and a stuff sack are UK made; everything else they sell is imported.
They have a specific military website at http://www.snugpak.com/military/
Rab sleeping bags are hand filled in their Alfreton warehouse (none of their clothing or other gear is made in the UK). I am not sure that really counts as being made in England though! Still though at least they are filled in the UK, so that’s good.
PHD (Peter Hutchinson Designs) sleeping bags are made in the UK. PHP make down sleeping bags, down jackets and mountaineering clothing. All PHP products are made in England – http://www.phdesigns.co.uk