Trauma Kit for Church

#1
I'm in the middle of helping my church put together a trauma kit(s) for the parish. I want to make sure it is sized correctly (300 each Sunday). Working in EMS, fire, and now law enforcement, I've helped individuals and very small organizations put together trauma kits in the past, but never something this big. Can anyone point me in the right direction on sizing a kit for a congregation of 300 people?