haha I always do major mods right before I need the car, I cant tell you how many times I have had to wait for the autoparts store to open the morning before I go racing. I have an ls3 but I've seen a few threads where others have stripped out 1 of the bolts so i'm sure you would be safe driving with it if you cant fix it right away. Not sure if you have amazon prime but you can 1 day ship it for a few extra bucks if you do, I think this is the size you would need but make sure to double check.
http://www.amazon.com/Helicoil-5546-.../dp/B0002SREP4