Minimum Hand to Call This ReRaise...

[nightlyraver]

This is a theory question, but it was inspired by an opponent from a tourney I played yesterday...

OK, say you're in the middle stages of a MTT with about an average-ish stack. No one is in the red yet, but everyone at the table has an M or about 8-14 with only one big stack at the table. The big stack as well as everyone else has folded and you open for a raise on the button. The small blind moves all-in. Your hand is not strong enough to call, so you fold. As time goes by, you notice that this same Villian has moved all-in after a player has raised in late position more often than she is entitled to, though not every time. Again, it's foled to you on the button and again you raise, hoping to pick up the blinds and antes. Again, she moves all-in.

Assuming that it costs you all or almost all of your chips to call, what are the minimum holdings you will call this with? If you want to steal, are you better off just moving all-in yourself in this same spot (it would be a big overbet) and put the pressure on the small blind?