Snapped off brake line screw..

[Trunkz]

Well, long story short, I was fitting the last braided brake hose, and in taking off the crappy rubber hose, i've managed to snap off the screw from the brake line, and now I need to get that sorted. Any ideas on how much this would cost? If anyone knows any garages in Surrey, that would be even better; need to get it done saturday / sunday by the very latest