I forgot about Naruto going Nine-Tailed on him, oh well
The sand armour takes chakra right? So if Haku keeps pounding away at it, Gaara will be drained eventually, then at the same time he could use any remaining chakra to release Shukaku... I'm trying to go on both sides right now because yes it would be close
I mentioned those throwing needles before, and here I go again.... What if Haku cracked the armour and then threw one in a crack? Couldn't he hit Gaara then? Of course Gaara has Sand Clones, too, so that could complicate things....
This is fun!