Hi Joanne,
Welcome to the Disney Parks Moms Panel! It sounds like you're going to have a spooktacular evening with your granddaughter!
Mickey's Not-So-Scary Halloween Party is my favorite Special Event at Walt Disney World Resort. I went just a few weeks ago and had the best time. Don't miss Pirates of the Caribbean because some extra pirates have shown up for the fun this year!
You can absolutely purchase a limited edition
MagicBand in the theme parks as long as the MagicBand is available. Some of the limited edition MagicBands sell out quickly. If I were you, I would check on the
Shop Disney Parks app to see if it shows any availability for the MagicBand you want to purchase.
Joanne, thank you for visiting us with your question. I hope you'll let us know if we can help you with any additional planning questions!
Wishing you a magical visit,
Amy H.