Combine the oats, rice cereal, cranberries and pistachios in a large bowl; set aside.
Melt butter, brown rice syrup, brown sugar and salt in a saucepan over medium-high heat. Bring to a rapid boil, and cook 1-2 minutes, until mixture thickens. Stir in vanilla extract (careful, it will sputter).
Pour hot syrup over the oat mixture and stir to combine. Allow to cool at room temperature for 5 minutes, then stir in chopped chocolate. Using a rubber spatula, press mixture firmly into a parchment-lined (or greased) 8" square baking pan (or you can use a piece of parchment paper laid on top to help you really press it down without sticking to your fingers). Transfer to freezer for 10 minutes until set, then cut into 18 bars.
Store granola bars in sealed container up to 5 days, or in the freezer for up to a month.