Position the oven racks in the upper and lower thirds of the oven and preheat to 350 degrees F. Line three baking sheets with parchment paper and lightly coat with cooking spray. Combine the oats, flour, cinnamon and salt in a food processor and pulse until the oats are finely chopped.
Combine the oil, sugar and maple syrup in a medium saucepan over medium-low heat and cook, stirring, until the sugar dissolves, 2 to 3 minutes. Remove from the heat and stir in the oat mixture, raisins and vanilla. Let the mixture cool slightly. Stir in the egg white.
Drop teaspoonfuls of batter about 2 inches apart on the prepared baking sheets. Sprinkle with the turbinado sugar if using. Bake until golden brown (the edges of the cookies will be a deeper golden brown), rotating the sheets about halfway through, 10 to 12 minutes. Let cool on the baking sheets for a few minutes, and then transfer to a rack to cool completely.