Amazon is my seller of last resort. Ebay has 'em, too; just need to wade in a bit as some sellers want waaay more than MSRP & some want more for a certain color, as in a couple of hundred more, which actually boggles my mind because the very first thing I do with a new phone is put it in a case, as in, not take it out of the box & set it up until I have a case to put it into so I have no idea what color is on the back. My preference is kickstand cases, which tend to be a bit thicker, too.
I was thinking about a regular retailer, a camera or electronics store? (B&H & only sells accessories, not the phone itself.)