I don't know too many thirdies. Sandoval might be good to nab, if Harry doesn't pick her. In our House, if we can't get Hydra, Warrington is sharp enough, and Bode carries herself rather well. I'd recommend them. What about the third-year Ravenclaws?

Bundy's quiet, but I think she'll try her best and won't rock the boat or be disagreeable.

I'd be free on Thursday night -- perhaps that'd be best, because it'd give us a day to look up any useful spells we might need after we settle on a strategy.