street price
/ˌstriːt ˈprʌɪs/noun
1The price at which something is available on the street. Hence (in later use): the price which something, especially a quantity of drugs, fetches when sold illicitly.
2The price at which something is available in shops, especially when this is lower than the recommended retail price.
Origin
Mid 19th century; earliest use found in Daily Sentinel & Gazette (Milwaukee, Wisconsin). From street + price.