Specialized Glasses Quetion About Glasses?

Quetion about glasses? - specialized glasses

My doctor told me that I needed glasses and gave me a prescription. I think he prescribed glasses 150th My question is: Where can I get these glasses? I went into the business, and glasses are sold in more than $ 100 because it has through the frame for free and then specialized to the recipe. Reading glasses I have also seen in other stores (ie, 150) on the prices as low as $ 5 sold. I've made, and with them I can read with ease the eyes. Is it really so? I do not mean the money I care, but I also prefer that people do not strive to take advantage because I know nothing about the glasses. Oh, and you go into the stores and shops that specialize in the tanks is not good because the sales staff are terrible, they know nothing about lenses, only the price. Thank you for your comments.