Minimum:
1200 AP
150 Hit
20% crit
all unbuffed
Ideal:
1400 AP
200 Hit
25% crit
I posted an edited pre-kara gear thread earlier today that is a few posts down on the front page of this forum.
Check it out. You don't need ALL of the gear on there, but about half of those pieces and the rest dungeon blues would suffice to start Kara.