Hello!!!
Finally the evad3rsdevteam released evasi0n - iOS 6.0-6.1.3 Jailbreak a new working untethered jailbreak for ios 6.1.3.Its evasi0n - Version 1.5.4 . i saw many people using this tool and jailbreak their device. you can look evad3rsdevteam (dot) com for your work. Hope this will work for You too. Do share this information on Social Media