i remember looking at those injectors when going to get a 1z 90bhp diesel.
they do sell them on ebay just type in the .216 injectors and you should get some hits.
theres probably a guide of how to do it online somewhere and wont be too difficult.
but to warn you, doing this and the remap will chuck out a fair amount of black smoke when accelerating hard, this can then be stopped by getting a bigger turbo
