I have to agree with Jock Scot; I've only seen one person (the late Lord Borthwick) wear a tartan waistcoat with a tweed day wear jacket. The only reason that it worked (in my opinion) was that the repeat of the sett of the Borthwick Tartan on the waistcoat was about one and a half inches, in other words much tinier than the repeat on Borthwick's kilt.

With a black Argyll jacket a black waistcoat, cut either for day wear (5/6 buttons) or evening wear (3/4 buttons), is the only appropriate choice.