What are Best place to buy Docsis 3.0 cable modem DCM476 ?

What are Best place to buy Docsis 3.0 cable modem DCM476 ? Hi Can you please advice me where is the best and safe place to buy a Docsis 3.0 cable modem. My internet service provider want $100 + $10 shipping = $124.3. A friend of mine got a modem on Kijiji , but it was a not working. and he could't return it back , So i'm afraid to buy it there. Does anyone know where i can buy it in Mississauga ? or Online ? ( if online can somebody recommend me where. please comment below....