Stats: DEX, STR, and VIT.
Get buffs, a Soul Link, a Poison Bottle. When you are SB kids going to realize your skill is grossly OP, anything you do won't matter, you'll always get a one hit kill.
And yeah, I'd love to know what kind of Lowrate you're playing where you have 2 MVP Cards readily available like that.
Oh, gear.
Armor: Doesn't matter, you're SB so obviously you're "leet pro pvp", you don't need no stinkin' armor. It'll only slow you down. Don't wear anything but a cotton shirt, because when your arms are waving all over the place landing your "pwn" damage everywhere, the last thing you want is for them to get tired, then you won't be able to lame people with SB anymore.
Weapon: Either that spec jur you mentioned or an Infiltrator, which is the weapon of nub--er...pro SB users everywhere.
Accessories: Make sure to wear a double client for priest buffs, blacksmith buffs. Wearing a Soul Linker on your back will increase your chances of winning.