Well you were pretty specific with your party set up Molly. You could have just as easily said "Grab a tank, some healers and some DDs that can attack right limbs."

To the OP: I would encourage you and your LS to go with whatever classes you guys like to play. Just make sure you have at least 1 person who can damage the right arm (this much is obvious.) If you do only have 1 person that can damage the arm, make sure s/he focuses solely on it the entire fight after you've killed the Bouncers (unless you're low-manning.)

The drop rate on the sword seems to be lower than other NM drops. Patience and persistence are the key here. You will get them eventually, if you haven't already. Best of luck to you. ^^