Well, generally speaking, you can buy them in many places such as the official stores. And the online shop which can be cheaper than the real shop. For example, you can buy them on the find shop. In this place, they have many different types and different colors. It all depends on your own needs and choice. So just link to http://www.thefind.com/jewelry/browse-zegna-sunglasses. For the prices, they vary from 150 dollars to 400 dollars. Of course, it can be kind of expensive, but they are worth the money, because of their beautiful styles and wonderful design.
It is not cheap to buy a pair of zegna sunglasses. Most of them are ranges from $200 to $400. And here are some online shop where provide zegna sunglasses. Just check it: http://www.visiondirect.com.au/designer-sunglasses/Ermenegildo-Zegna/
Well, you should know that Ermenegildo Zegna is one of the most renowned luxury brand in the world. It is famous for its top quality stuff and feeling. Of course, you can find them at some large shopping center in large cities. However, not every store has got them on offer, so I suggest that you visit some e-commerce websites for some information, perhaps there are lots of zegna sunglasses.