I know, I know. I am already 6 months into the bike trip, almost to Guatemala, and something the trip keeps trying to teach me is not to make plans far in advance. But I've gotten very caught up in the idea of sailing home, so whenever I have spare internet time I try to learn more. I just thought if someone answered this I would have a better idea if I'd have to give up on the plan. I have a rough idea of when I will be in Argentina, and honestly if the consensus here was that in, say, November it would be easy to find such a passage but no later, then it would be worth it to me to try to get there by November, even if that meant taking a bus or not going all the way to Ushuaia.
Thanks for the equipment advice.