Turbinado Sugar is type of "raw sugar" made using cane sugar from the initial pressing of the cane, allowing the natural molasses to remain in the crystals. The resulting crystals are steam-cleaned to remove any contaminants but retain their slightly light brown color.
If you don't have turbinado sugar you can replace it with:
Walmart carries turbinado (sugar in the raw) online. Trader Joe's sells their own brand too. You can also purchase it on Amazon.com: Turbinado Sugar