Are you planning to make a stop at
Walmart when you go? We usually stop the first day for grab and go breakfast items, snacks, etc. The Walmart we went to in April had a large selection of adult and kids ponchos, with Disney characters (Mickey, Minnie, Goofy, Star Wars) for like $3 each. And they're actually a pretty solid weight too, I used mine in April and it's going back in my bag again for my trip this week. Cheaper and nicer than the dollar store ones!