You could start by looking at the dealers who support this forum by advertising here, and most of the dealers here can supply DBA and other makes, DAN big brakes for example, Abbey Motorsport, Rising Sun Performance and others. Good pads might be Ferodo 2500's, also available from the same sources.
For me the best value has proven to be DBA with the Ferodo pads, but all of the dealers here have options and no the umpteen variations so no cock ups.
Aitch