ZTX605 Or Equivalents (2SD1579, 2SD1659,2SD2213)

I'm looking for an equivalent to ZTX605 NPN Silicon Planar Miduim Planar Transistor Darlington Transistor (Data Sheet attached) or equivalent for a project I'm working on. I'm actually using it to introduce a delay in switching my 12V relay. Can't find it or the equivalent in Nigeria, will be grateful if any other transistor can be adviced. The circuit schematic is also attached.