I guess I'll be the guy that makes the obligatory remark about how appropriating another person's property/identifying emblem, etc. is in bad taste, despite the fact that it is done routinely by Americans.

Because of that, MacLL, I urge you to be the "heraldry ambassador", explain that there is no such thing as a coat of arms for a surname, and encourage them to use the clan badge for the Chief of the Colquhouns, instead.