I'm guessing double barreled alas Balvinnie and company. I think a lot of the Sherry/Port Cask practice is just marketing to be different and to latch onto McCallums success. Christ even the Irish are doing it.
Lagavulin does market a cask or distillers version - basically an 8 or 12 year old, can't remember.
They also have also had 30 and 40 year old that can get fairly expensive,
I don't believe we can get them at the LCBO any longer and they may be difficult to find, I would expect $500 to $1,000 per bottle.
That's why I prefer the 16, a nicely aged, incredibly deep and complex flavour with a huge nose for a mere $125