OEM will be local Honda dealer. Or try Hendys, Steeles, Coxs etc.
EP3 springs will fit PFL, but not shock i think. Sure someone will come and confirm this soon. I think you can use EP3 coilovers with some mods, not sure about oem, also not sure oem would be the same spec, damping wise.
Spend some time having a read through the forums, as almost anything you can think of, has been asked.
Also its a good idea to get your self a copy of the
RSX Manual