Apex Battery offers two DXG-308 chargers

http://tinyurl.com/2fstzxp

laptoptraveler.com has a charger they say is compatible with the DXG-308

http://www.laptoptraveller.com/battery-dxg-dxg-308-digital-camera-accessories.html

You can bypass the need for a USB cable with a card reader. That also saves wear on your camera.

Search Amazon.com for "card reader" and choose one compatible with your memory card