I'm guessing 50's. Would you be able to post another picture of the label. The bottom part looks unusual but it a little blurred. I presume it say " not a drop sold until it's 7 years old" but they usually have it in 3/4 lines. That looks like 2 lines.
I know there was lots written here about the fact the it has Dublin Whiskey on the label. That may narrow down the search. My knowledge about these are limited. I'm better with the 12's.