I actually have a short-sleeved black St. John that I was on the fence about bringing with me (I am going on a cruise on Saturday, and it could work for one of the formal nights). If I wear it on the plane, problem solved. I could buy an inexpensive wristlet at Bendel's tomorrow (my hairdresser is above them, so I have to pass through). Not a bad idea.
Thank you for all the ideas, ladies. I am having a hard time wrapping my head around all of this.