Hi Ian ,
the transistor is basically a surface mount version of the BC108
if the pcb design makes it possible ,you could try a TO92 plastic NPN transistor like a BC547 or BC548 (can try maplin for this)
otherwise try ebay , RS components or farnell for a BC848
what is the transistor used in ,and how many do you need ?
I may have one or two SMT transistors that may work
John