They moved from Little Chalfont to Reading under a new name, A2 Supplies, and are attached to the Mall. Whether its the "same" company now I'm not sure, but the same guys work there. https://a2supplies.co.uk/
The key to building an impression kit isn't spending all your money at once. Live within your means and build it up carefully and you'll be so satisfied when it's done. Plus the big money pits, like the rig set ups, can be easily switched for replicas and still look great, TMC JPC/AVS/CPC etc are decent enough for airsoft and relatively cheap (compared to the Crye equivalents anyway). Same for the helmet, no need to spend £££s on a real opscore, just grab an FMA repro, and build off of that.
Literally one plot foiled per week that you'll never read about because it doesn't sell newspapers. A whole war in the middle east for 10 years because of terrorism with 500 UK soldiers dying for little to no reason. More specialised armed response units than ever before. Just bear in mind that this is the sort of thing UK intelligence is supposed to deal with - if you're catching a bomb in a suitcase at the airport or needing to shoot someone then there have already been a handful of other failures between the making/importing of the bomb, communication of the perpetrators etc. that weren't caught. These are things you don't see because - again - they're either not disclosed immediately or don't have a series of gore-y videos and pictures that they can slap on the front of every tabloid for a week.
It's not that no one is doing anything, it's that you're not reading about it. Increase your breadth of media consumption beyond Facebook and be realistic about the figures involved here. People like you are exactly who terrorism preys on. Whilst this is a problem, it's absolutely blown out of proportion every time to give the murderers exactly what they want - that's the really injustice here.