10man? Flex?
Ideally 2 tanks, 3 healers and 5-6 dps. No more than 3 melee dps tho.
You can take up to 13 people to Flex before the tactics switch to 25man versions.
I will probably be available on a 510+ ilvl disc priest if you need another healer. Let me know and you can invite xrealm etc.