Projector lamp A1 240V 150W (Cholsey/Wallingford OX10)

In time-honoured fashion, the bulb blew just at the start of the slideshow. Does anyone happen to have a spare of this sort of projector lamp? I understand that it's Type A1, 240 Volts, 150 Watts, with a BA15S bayonet-type base. Sylvania (maker) refers to it as 'blue top' for pretty obvious reasons.