Sirius has an app for smartphones. If you have decent data available you could stream the game on your phone. Plus I think they give away free trials!
This sucks. I'm gonna miss the Cards-Braves game today while driving to Dallas to look for a new apartment, and I'm gonna miss Nats Game 1 while driving back. Rooting for a team since April 2005 only to miss its first-ever playoff game.