The Sony Xperia Z (http://www.gsmarena.com/sony_xperia_z-5204.php) is now officially available through the Sony online store in the US. You can get the HSPA+ model unlocked for $629.99 in all three colors: black, white and purple.
(http://st.gsmarena.com/vv/newsimg/13/05/xperia-z-us/gsmarena_001.jpg)
Meanwhile, the Sony Xperia ZL (http://www.gsmarena.com/sony_xperia_zl-5203.php) got a price cut. The phone is now available for $629.99 from the previous $759.99. The Xperia ZL is similar to the Z but lacks the water-proof design and the glass back.
If you are looking for a better deal, though, you will find both phones for a lower price on Amazon and Newegg.
Xperia Z (http://store.sony.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10551&storeId=10151&langId=-1&productId=8198552921666561651)