Used Toshiba THNSNS128GMFP 128 GB Proprietary Apple PCI-E 3.0 x4 SSD - Walmart.com
Amazon.com: Sintech 26pin to SATA Adapter with USB SATA Cable,Compatible with SSD from MacBook Air Pro 2012 Year (NOT fit SSD from 2013-2015 Year) : Electronics
SSD Flash Drive 128GB Toshiba-MacBook Air 11" A1465- TEKDEP.com Parts Tools Gadgets Repair
The New MacBook Air Uses Toshiba's SATA 6Gb/s SSDs UPDATE: Samsung Too
M.2(NGFF) SSD 8+18Pin adapter as SSD of 2012 MACBOOK Air [ST-M2A2012-S] - $10.99 : Sintech Eshop!, The World of PC Adapter Card
Tested A1466 A1465 64GB 128GB 256GB 512GB 2012 Year Solid State Drive For Macbook Air 11.6" 13.3" Laptop Motherboard SSD EMC2558