Are hi index lens available? Also, is prism an additional charge?

They are available at http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/http://www.eyeglassesclub.com/, in general, they charge $20-$50 for extra prism based on your prescription.