adapter - PCI-e to PCI with flex cable - Server Fault
StarTech.com 1-Port PCI Express RS232 Serial Adapter Card - PCIe Serial DB9 Controller - Low Profile - PEX1S553LP - Serial Adapters - CDW.com
Amazon.com: PCIe to PCI Adapter Card,PCI Express x1 to PCI Single/Double Converter,PCI-e Extender Card with USB3.0 Cable for Desktop Sound Card (PCIe to Single PCI Slot) : Electronics
PCI e PCIE to SATA Card PCI-E Adapter PCI Express to SATA3.0 Converter 4-Port SATA III 6G Expansion Controller Card Adapter IPFS - AliExpress