How much dose a vintage bottle of Hennessy Cognac sell for?

i was helping my grandmother move out and she gifted me an unopened bottle of BRAS D'OR HENNESSY COGNAC, she found in her basement. its 700 ml., 40 prof. and on the back it says it was bottled August 2nd 1956|||CALL LOCAL LIQUOR STORE FOR HELP TO FIND OUT|||OVER 5 GRAND