go to newegg.com and get the Real Blackberry Car Charger, it comes in Authentic Blackberry packaging and is not an off brand and no danger of hurting your Blackberry.
I got one and it is the exact same charger you buy from Blackberry's Store online. It is authentic!
Look for item number N82E16875999266 on newegg.
The home charger they sell is original BB also, it ias the same as came with my 8330.