Musannaf Ibn Abi Shayba 13:2231

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Sharik narrated to us, from Simak, from Ikrimah, from Ibn Abbas, who said: A caravan arrived in Medina, and the Prophet, peace and blessings of Allah be upon him, bought from it. He made a profit of awaq (ounces of silver), and he distributed them among the widows of Banu Abd al-Muttalib. And he said: "I do not buy anything for which I do not have the price."