You get a few around east london, but they few and far between. PE also has them, but also not pletiful, except in places like the dolos on the harbour wall. seen plenty there, but no chance of getting them out. Not 100% sure of further south as havnt dived there.
Nepps, when you where allowed on the wall we used to dive them out. Caught the odd one on the line. Biggest i saw come out while diving weighed just under 2kgs. If you have a duck you can dive them out, but have to dive when the swell is small and you have to watch for the little sharkies as they bite your flippers while your head is in the dollosa!!