Amazon.com: GODSHARK 7+17 pin mSATA to A1398 A1425 (2012 & Early 2013) Adapter for MacBook Pro Retina SSD Replacement, Mini PCIe SATA SSD Converter Card : Electronics
Amazon.com: MCE Technologies 2TB Internal SSD Flash Upgrade for 13" and 15" MacBook Pro Retina (Mid 2012 - Early 2013) - Includes Installation Kit! : Electronics
How to Upgrade Retina MacBook Pro SSD Storage: 13-Inch: EveryMac.com