Little tough to see in the image but how boogered is the existing hole? My concern is going with the same size and having it not grab since the damage is there. I would still give it a shot with the right size and if it doesn't work, well you know you need to go bigger. I wouldn't go with a locking type of helicoil as if it gets screwed up (stuck, etc), you are definitely going to have to drill it bigger vs trying again.
Maybe they have this local to you but double check the bolt of course before swiping the card -
http://www.autozone.com/test-scan-an...tem/516477_0_0