So far I have 3 pre assembled small kits that I have added to my gear.
My first was the Ultimate Survival Deluxe Kit I wanted a saw with a bit more grunt than the wire saws, and this is what I found available down here (Australia) and the other items make a nice little kit.
The next I adde was a BCB Combat survival tin. I'd herd a lot about these, and when they became available here I bought a couple. I ratted the wire saw for my already self assembled PSK tin because it was better than others Id found, but everything else I had already covered, so it was a waste, but I have a small stock of spares <img src="/images/graemlins/smile.gif" alt="" />

My recient addition has been the ETS PSP. There is a place over here importing them now (still waiting on the RSK Knife & the Photon) Ive found this a fantastic little kit. It fits better than a tin in my pockets so I carry it more than my other kits.
My only hassle with it is that the pencil is sharp, and being in my pocket it has damaged the foil and clouded up 1 corner of the pack with graphite. Nothing a bit of duct tape around the tip of the pencil wont fix, and it comes with enough to solve that problem <img src="/images/graemlins/smile.gif" alt="" />
I dont know what small kits you do have available to you, but I would recomend the ETS PSP, even if you have to ship it overseas. Look at the ETS page to see if they ship to the UK thats how I found them in Australia. The BSB Combat Survival kit is a good starter too, but the ETS PSP is better.