I have seen lovely ones in piercing shops, with diamontes in then.
The shops aren't as scary as they look on the oustide, by the way. I've always dealt with lovely people in them.
There's a posh place in South Ken or Chelsea I think - some sort of piercing/ tattoo place to the stars, but not very expensive. Can't search online for you as my work firewall blocks that kind of "fetish" stuff.