Hi Will,
Looks like you might have an interesting bottle there. It would be very interesting to taste all right. What's the fill level like?
It could be very hard to descern actually what or where it came from.
Although it does say a Blend of whiskies it could well be a blend of pure Pot Still whiskies so that could be a bonus.
However it is probably a bottling from the time when the company was wound uop and the stock went to the four winds. Therefore mix will be very hard to figure out whether of young or old or medium aged whiskies or even a bit of everything.
Obviously from the states going by the Vol of 750 and 80% proof (40% abv)
If you need a hand drinking it give me a shout