I bought an oem Palm car charger for $4 shipped, it works fine as well, any 5v micro usb charger will work, but I recommend a quality one that can give 5v/1a. Some chargers give less than 1a, and will still work, but will charge at a slower rate, even perhaps at less than power draw, depending on usage.
Sent from my Verizon Wireless 4GLTE HD smartphone.