There was an EE place in Whitechapel almost a decade ago that did them for £25 - WGs were quite decent too and they seemed to be operating out of someone's place of residence so I got to do the deed while a child's teddy bears looked on.
And just to make it even more surreal, while I was on top of her the maid walked in clutching a fiver saying "It's OK, I found your chaaaange." and laid it on the bed.