My new Orphans Arms shirt.  I love this company and would happily accept any of their garments as gifts (hint hint).  True, their "Queen of London Whoredom" shirt might be a little difficult to wear in mixed company, but I'm sure I could think of something.
Obviously when one thinks of England and magic, one thinks of Harry Potter, so I amused myself today by telling people a fanciful backstory about the London School of Sorcery - sort of a vocational college for the working class wizard (in other words too cheap to go to Hogwarts).