I understand the appeal of wanting matching accessories - I'm often the same way myself.
For a charger, what you care about is a clean 5V, .5 to 1A (500mA to 1000mA) output - they're typically 1A. My HTC Evo phone has a nice charger with a USB cable that comes out, so I have in one package a nice way to charge from the wall or my laptop. HOWEVER - I really prefer the less-tight plug from old Samsung Moment charger. Hoping that info gives you ideas if you can't find exactly what you like.
Usually, when people say battery extender, they often mean an over-sized battery and a replacement back cover to accommodate the thicker battery. Sometimes, you can get a slightly-higher capacity battery in the same size. So - it might be a little dependent on the conversation.
Some of the staff is busy with MWC in Barcelona this week, but if I hear anything, I'll post back here for you.
Just to be on the safe side - what's your phone model, please? If you're uncomfortable saying in public for any reason, it's ok to PM me that info.