Good help, and thanks! I would not have asked for information if I weren't interested in getting the banner right (they are too expensive to get wrong). It seems that the Clan Badge is the thing, which is very fine.

I do see a need for a banner with the Clan name, and that is neither mentioned, nor as far as I can tell, regulated. It is not heraldic at all, but a practical banner. A bit of tartan, some words, I'd think those were fine.