Even if handguns were still legal here it would be highly illegal to smuggle them in from America.
Hmm.
While I must admit be being an enthusiast for the 1911A1, I must also admit that many of the world's finest semiautomatic pistols come from central Europe (Germany, Switzerland, Austria, Czech Republic).
Seems like it would be easier to smuggle them in from the continent.
Oh, and if a Peshawar tribesman can manufacture a highly functional semiautomatic pistol with hand tools, I suspect that there just might be some Brits left with the competence to replicate such performance.