Combine all ingredients (except sea salt and lime wedges) in a powerful blender. Blend using the ice crush setting until a slushy texture forms. Add more ice if needed to make about 32 fl oz (a little less than 1 L) total (for four 1-cup margaritas).
Run a slice of lime around the rim of each glass. Dip the rim into a plate or shallow bowl covered in sea salt. Pour frozen margaritas into the glasses and garnish with lime.