Proc Weapons Follow

To be honest you can use pretty much anything. Just go to the auction house and get cheap weapons from each catagory. I just use a bunch of stuff I already had.

Dagger - Buccaneer's knife from when I would kill Brigandish Blade.
Sword - Joyeuse which I would use when dual wielding for fun.
Scythe - Beluga which I got from a chest in Zi'Tah.
Staff - Earth Staff which is nice for the -20% pdt.
Polearm - Engetsuto which I had when I needed a piercing weapon for war.
Club - Warp Cudgel which I always have anyways.
Great Sword - Ferrara which I had from killing ZNM.

Like I said, just go the the AH and find some cheap weapons from each catagory if you don't happen to have something already.

Dagger - Yataghan
Great Sword - Ferrara, Perdu Sword, or Algol (whichever I happen to pull out of the sack when it's needed)
Staff - Jupiter's Staff
Sword - Joyeuse
Club - Vodun Mace from Dominion
Scythe - Misareaux Gold Chest scythe w/ Acc+9
Polearm - Iron Ram Lance

I got caught off guard on WAR yesterday and had to proc staff for blue. I wasn't prepared to be asked for this quite yet on WAR since I haven't skilled up many of the weapons and so I didn't even think I had a staff on me. Luckily, I was carrying a 1-damage republic signet staff (which was hitting for about 5 damage), got enough TP, and succeeded in the proc. And sure I guess I could have borrowed a fire staff or something from a mage, but it was the principle of the thing of preparedness here!

You don't really want to be doing damage with these weapons since proccing can eat up a lot of mob health so I wouldn't go getting fancy stuff. Anything you have laying around that you carry anyway is fine enough, and a few weapons that give unique advantages and are easy to get (like earth staff) fill out the list. If you don't have either, go cheap. No point in sinking gil into something where damage doesn't matter and I certainly wouldn't camp anything.