Lehor collects antique cars. He contracts to purchase spare parts for a 1938 engine from Beem. These parts are not made anymore and are scarce. Lehor agrees to pay 50 percent of the purchase price in advance. Beem, informs Lehor after receiving the payment, he found another buyer willing to pay substantially more for the parts, and tells Lehor he will not deliver as contracted. What possible remedy is available to Lehor to enable him to take possession of these parts