Musnad Abu Ya'la al-Mawsili 42:254

Abu Khaythama narrated to us, Yahya bin Sa'id narrated to us, from Ibn 'Ajlan, 'Iyad bin 'Abd Allah narrated to us, from Abu Sa'id, who said: "I will never give out anything except a sa'. We used to give out during the time of the Messenger of Allah (may Allah bless him and grant him peace) a sa' of dates, or barley, or dried yogurt (aqt), or raisins."