Black And White Scotch Whisky

I have an old bottle of "Black and White" special blend of Buchanan's choice Old Scotch Whisky with the number on the bottom of the bottle; NB125 N 23 UGB. Scotch Whiskey Distillers...Glasgow & London ..Glentauchers Distillery, Mulben, Speyside.The bottle is dark green with Black and White scotch Whisky engraved in the glass and has wire on the cap with a heavy white shrink label. There is a label at the neck which says"By appointment to her majesty the queen..." The back of the bottle also has a label with the two dogs sitting on a plinth. I wonder if anyone could help tell me how old it is and the value.