Hi James. Have a look at www.gunsite.co.uk Theres a couple of clubs listed that may be of use to you. It may also be worth calling Kranks in Pudsey. I know Roger at South Yorkshire shooting supplies used to shoot a b/p pistol so it may be worth calling in and enquiring what club he uses. There is a club at Reapham in Lincolnshire but that will be too far away i suppose.
Good luck with your search, Tim