Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates: The Prophet (peace and blessings be upon him) said: Do not sell one dinar for two dinars, do not sell one dirham for two dirhams, and do not sell one sa' for two sa'. I fear rama' for you. (The narrator says:) "Rama'" means usury (riba). A man stood up before the Prophet (peace and blessings be upon him) and said: O Messenger of Allah! What is your view of a man who sells one horse for several horses, or a fine she-camel for camels? The Prophet (peace and blessings be upon him) said: There is no harm in it as long as the exchange is hand to hand.
Ahmad recorded it, and al-Tabarani recorded something similar in al-Mu'jam al-Kabir; its chain contains a narrator, Abu Janab, who is thiqah (trustworthy) but a mudallis (one who conceals defects in the chain).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب البيوع / 6553