Your guild should be the ones who would help to raid the plane these drop on. Make your needs known, and keep an eye out. You can expect to roll for the drops you need. When I got mine, yes, it was a full scale raid and we cleared the land... and skies. The raid lasted two days. One Sphinx Crown dropped.
Ok, stupid question time... Should I presume that we have to mount a full scale raid on PoA just so we can try to run some of these quests? If so, can I get some tips or thoughts on how it is suggested that we do all this and collect the requisite parts duing the space of a Raid?