There aren't many real shops left these days but Keith Bennett has one - check out
www.kbmagic.co.uk for directions and details. It's a small shop and easy to miss but look carefully - he's open Saturdays but not sure about any other days! I saw one last year on the Bristol Road almost opposite Sainsbury's at Selly Oak - he did juggling items as well and I think Friday night was late night but no idea of the name. There's one over towards Wolverhampton and the name has escaped from memory on that one as well but I'm sure HT will be able to remind me!
Failing that, The British Magical Society (who are older than the Magic Circle!) are based in Brum and may be able to advise - do a Google search for them or there might be a link from Keith's website.
PS Welcome to the forum!