You may be able to get a replacement cover now, but there's a good reason to wait
One of the hotter topics in our Galaxy S5 forums today is the different colors of the Galaxy S5. Specifically, it's that the battery door for the white model is more of hard plastic than the softer black cover. (And if you can find the blue, I highly recommend it. It's so nice.) So, folks are hunting around for replacement battery door covers. Black on white should be pretty good — and blue on white may be even better.
And we're starting to see doors pop up on eBay, imported from China.
But there's a catch. And one that you need to be aware of before putting these covers on your phone.
Pay particular attention to the item description and pictures. For the ones we've seen so far (here and here), there's no rubber gasket on the inside. And that means you won't get the proper IP67 rating against dust and water. (That goes for this sweet-looking brushed metal number, too, it seems. It might be noted in the item description — it is in two listings we've seen — or it might not.
So be careful. You'll probably want that gasket. We'll keep digging, of course. But in the meantime, caveat emptor.