I put a bunch of money for the trip on my Starbucks card too, because I'll totally need coffee for the drive. I also mapped out all the SBUX along the way. LoL...
You might be in luck there, I know Disney is adding a Starbucks to the Main Street Bakery over in MK which MIGHT be open by the time you arrive. It should be within just a few weeks now and epcot is getting one within a month or 2 if I'm not mistaken.