Amazon.com: Transcend 240GB JetDrive 725 SATAIII 6Gb/s Solid State Drive Update Kit for MacBook Pro 15" with Retina Display, Mid 2012 - Early 2013 (TS240GJDM725) : Electronics
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Amazon.com: GODSHARK mSATA to A1398 A1425 (2012 & Early 2013) Adapter for MacBook Pro Retina SSD Replacement, Mini PCIe SATA SSD Converter Card : Electronics
How to install an SSD on a 15-inch Retina MacBook Pro
Amazon.com: Odyson - 128GB SSD Replacement for MacBook Pro 13" A1425 / 15" A1398 (Late 2012, Early 2013) : Electronics
Amazon.com: MCE Technologies 1TB Internal SSD Flash Upgrade for MacBook Pro Retina (Mid 2012 - Early 2013) - Includes USB 3.0 Enclosure for Original Drive & Install Kit! : Electronics
MacBook Pro 13" / 15" Retina 512GB SATA SSD Solid State Drive, Mid 2012 / Early 2013 - 661-6487 661-7010