4tb Aura Internal PCIe SSD Upgrade and Storage Solution Late 2013 Mac Pro 6 1 for sale online | eBay
OWC Solid State Drives - OWC Digital
OWC Aura SSD for Mid-2013 or Later Mac - OWC Digital
Amazon.com: OWC 2.0TB Aura Pro X2 SSD Upgrade Compatible with Mac Pro (Late 2013), High Performance NVMe Flash Upgrade, Including Tools & heatsink : Electronics