Ok, for _all_ accessories like that there is one and only one place to go - Monoprice.com
For only $4.05 each when QTY 50+ purchased - 1 Port USB Car Charger 2.1A - Black
Buy the usb cable you need separately - and if they don't have it, it's either not made or going to be hard to find. (The Samsung cable was ultra-thin and slinky, but only available as a shorty.)
Low prices, high quality stuff, the darling site for HD fans.
edit - see also