Would anyone know of a SD card reader that has a PCIe interface for an expansion slot?
Any reason why USB or other such options are undesirable?
If it's about performance, most SD cards would not perform any better with a PCIe reader vs. USB 3.0 or higher (or perhaps even USB 2, at least for lower-end cards).
Mainly to prevent me from losing it. It sounds silly but I've lost multiple USB ones before,
Do you have enough ports to just leave a USB one plugged in?
Apart from a USB 3.1 gen 2 C no