Musannaf Ibn Abi Shayba 28:339

Humaid ibn Abd al-Rahman narrated to us, from al-Hasan ibn Qays, from his father, who said: I came to Ali with a cousin of mine and said, "O Commander of the Faithful, assign a stipend for this one." He said, "Four," meaning four hundred. I said, "Four hundred does not suffice for anything; increase him by the two hundred that you increased the people." He said, "That is for him," and he had indeed increased the people by two hundred.