I think you could probably get the JDM LSD from Brian Wong (bwsf@hotmail.com), but the rest I'm not sure.
I imagine that the price would be about the same cause they have to take the Diff out to install the PG anyway, so it wouldn't cost any more to get a whole LSD put in.
Let me tell you guys, I've been trying for the last few days to get my tranny apart and it is a BEOCH! I think that I'll just take it to a shop cause I really don't want to mess the thing up.