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 Retina: Upgrading to SSD (Howto)
Amazon.com: MCE Technologies 2TB Internal SSD Flash Upgrade for 13" and 15" MacBook Pro Retina (Mid 2012 - Early 2013) - Includes Installation Kit! : Electronics
Amazon.com: Sintech M2(NGFF) SATA SSD Card,for Upgrade 24Pin 2012 Year MacBook PRO Retina SSD (Fit M.2 SATA 2280 SSD,Not Fit M.2 nVME SSD) : Electronics
MacBook Pro (Retina, 15-inch, Mid 2012) SSD Upgrade - A Leslie Wong Blog
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