Musannaf Ibn Abi Shayba 7:210

Waki’ narrated to us, from Shu’bah, from al-Hakam, from Ibrahim, who said: If he says, "It is a gift to a pillar of the pillars of the mosque," he shall give its value or its price. If he does not find [the means to do so], he shall give as a gift what his wealth reaches, and he shall offer expiation for his oath.