Along with Cadenhead's,
Gordon & Macphail of Elgin has long been ageing and bottling mostly Single Malt Scotch. They do however pop out with a rum now and then. The last bottling I'm aware of was a Demerara distilled 1974, aged and bottled in Scotland in 2005. Here is a PDF link to their website
Tasting Notes. There may be a few bottles of this still kicking around Europe and elsewhere.