This is the Tri-ang Minic Ships model of the SS President Buchanan a Mariner Class C4 cargo ship owned and operated by American President Lines between 1959 and 1974.
The Mariner Class C4 cargo ships were designed in the early 1950's for the US Maritime Administration (MARAD), under the leadership of Admiral Edward L. Cochrane, to provide a nucleus of fast sealift capacity for the US Military after the limitations of the World War II era Liberty / Victory Ships were highlighted by the Korean War.
A total of 35 ships were built to the Mariner Class C4 design under a commercial arrangement between the US Maritime Administration and various American shipping lines such as American President Lines, Matson Lines, Pope & Talbot Lines, and Pacific Far East Lines whereby the US government provided some of the funding and the ships were available for call up.
The model is marked on the underside with the Tri-ang Minic logo, "Modern Edition", model number P 610, and the description "Mariner Class Cargo Ship".