Mrs E McWhinnie

I am looking for information please on behalf of a friend, whose husband was employed at Buchanans (he died over 30 years ago)She has a bottle of Buchanan's de Luxe blended Scotch Whisky, 70 proof , 26 2/3 fl oz. There is no age on the bottle but the number on the label is 75/297. any information and possible value would be appreciated. Thanks, Mrs E McWhinnie