I once dated a girl that stripped my float needle... but that was different.
It looks awfully thin to re-tap it. If you have dripped and tried to extract it, try putting in a pipe cleaner or very small wire brush into the hole with some lubricant. Turn it counter clockwise and see if you can get what looks like old thread out. If the threads in the carb are still not grabbing, maybe a self tapping metal screw? It will take work to get it into solid metal, but it may save you money.
How did you break the head off anyways? I hope you weren't using power tools... always ends badly IMO.