In the fall, I saw several reviews of the Sony PRS-T3. I've noticed the device is for sale in England and Australia, but the US Sony Store does not list it.
Will the PRS-T3 be sold in the US and when will it be available?
According to this article, never.
"Sony will not be offering the Reader PRS-T3 in the United States. In response to the region’s market changes, Sony will be focusing instead on mobile and tablet devices, including the Xperia Tablet Z and Xperia Z smartphone. Digital reading and eBooks remain an important priority for Sony. Reader Store will still help book lovers find and read their next story, anytime and anywhere, and customers can continue to expect new and exciting features and discovery tools. Reader Store will continue to support previous Readers as well as other compatible devices via the free Reader apps for PC, Mac, Android and iOS."
This is maybe not what you are looking for, but although the PRS-T3 is currently not be sold in the US, you can always buy it from the USA. This works the other way around as well: I got my PRS-700 from the USA in Nov. 2008, as it was not available in Europe.
Take care which shops you try. SONY's online shop and other online shops that are operating in the country of destination as well, will often not ship to such countries.
You could try and become a global shopper e.g. here: Tchibo.
Or you could try a seller on eBay, they often care even less than official outlets of devices about where they have to ship to.
Sony is leaving the e-book market outside Japan. You can use a forwarder in Japan to purchase one directly from Sony. There are also several site specialized in purchasing and shipping Japanese goods to foreign countries.