Rogue Galaxy Quarry: Rogue Pirates
The closest save teleporter to reach the Rogue Pirates is Salgin - Spaceport Entrance. From here you enter you'll want to head outside to where I am on the map. This is the location that you'll be able to summon the Rogue Pirates at.
The item needed to summon the Rogue Pirates is a Lucky Clover. This item starts to drop fairly regularly after chapter 8 or 9.
If you are missing the item required to summon this boss grind some battles and cross your fingers or go treasure chest hunting on a planet you've 100% the map on. In Rogue Galaxy once you pass a certain chapter the loot table of items that can drop for you ingame is updated.
What I mean is, every item has a chance of dropping off every creature after you've passed that chapter that allows that item to drop. At least this is how it works in my experience. Therefore, if you're missing any items to summon any of the quarry bosses all you need to do is grind a little until you get that item to drop for you. Good luck!