Any of the 5 cylinder 150 hp ones, or you could just buy them new from somewhere like darkside developments. I think the engine code was AEL
The injectors are mechanical and they're two stage, the fuel pressure just builds up then the initial stage begins then the main stage so they're much better to be set up so they all work at the same pressure, all balanced. it means you get the best from them otherwise you'll probably just smoke or could even ruin the pistons from them getting washed with to much fuel. It's called pop testing. Darkside charge £125 for the job which isn't to bad. Mine cost me nearly £300 after import duty etc and that was also getting them in a sale but they're good for about 200bhp with the right setup.