Fuel leak at injector, need nozzle or holder?

[anderson82300D]

I have a significant fuel leak at one injector site. I attached a picture because I'm hoping someone can tell me a bit more about the injector assembly. To me it appears that there is some sort of gasket or seal that is crooked in the center of the injector holder, but I wasn't really aware that there was one from what I've read. One pic is of my leaking injector, and the other pic shows a non-leaking injector's "seal".
All in all, I guess I need to know what I need to replace... I've only seen the nozzle on it's own, which is cheaper, or the entire injector, holder and all, more expensive but would certainly solve the problem.
Does a new nozzle come with the gasket that appears to be damaged on mine?