From Amazon
StarTech.com PEXUSB3S24 2 Port PCI Express (PCIe) SuperSpeed USB 3.0 Card Adapter with UASP, SATA Power, Dual Port USB 3 PCIe Controller
Novatech
StarTech.com 2 Port PCI Express (PCIe) SuperSpeed USB 3.0 Card Adapter with UASP - SATA Power
This product is also available at 6 unverified merchants.