Ballantine's Finest

Hello,
i just recived an 75 cl ballantine's bottle of its finest.
The man who gave it to me told me, it should be some 30 or 40 years old.
He's arround 80 years old, his mind is clear like mine (if not more, retired MD doctor) so there's no chance not to belive his words.
Anyway, i tried to determine the age, i like to know what i'm drinking.
the EAN code on the side 5010106111451, the number under the ean code is 3LK127F (maybe production run?)
I googled under those numbers, ean code gave me what i know already, it's ballantines.
howewer ist's strange that ean code from those years is still the same as today?
on the bottom of the bottle there are numbers SD571, and on the box's bottom besides ean code 5010106111536, there's written K 00536 (next line under)45470
The paper box looks worn, so it could be really old, but it could be also just dirty and misstreated.
So, is there any data base, from which the age of the bottle could be found?
I tried to find the appropriate image on the web, looks like this one (besides different volume and without "duty free sales" on it.
http://www.scotchwhiskycollector.com...es_finest.html
Thanks for your help,
El Barto