Sealed Old Black & White whisky

My Husband cleaned out his great grandfathers house, Which we assume belonged to his great-great grandfather. No one has been in this house since the late 60's.

In there amoungst many antiques we found a sealed bottle of whisky. It still has the federal revenue seal across the cap, and has never been opened. The reserve is 563375013. It is a metal spring cap I think. White lable.

Can you tell me the appx year and value?

The main lable on the FRONT of bottle reads:
By appointment to her majesty the queen
scotch whiskey distillers
james buchanan & Co. Ltd. London
Black
&White
Buchanan's
Blended Scotch Whisky
distilled blended and bottled in Scotland
Signature of J. Buchanan
Distillers Glasgow & London
Glentauchers distillery mulben spayside
Product of Scotland
4/5 ---- Cant read this line from wear on lable
100% scot.--- more wear on lable
WH---more wear
86.3---more wear

BACK:
White Diamond
Black
&White
Scotch
Whiskey with a black and white scottish terrier