See forum post: https://community.frame.work/t/another-sd-card-reader-that-can-be-made-to-work/33475
SD Card Reader Expansion Card for the Framework Laptop. Uses a generic Apple knockoff card reader for the electronics. These seem to vary slightly in their PCB size so you may have to modify this. For this model the specific reader I bought was: https://www.amazon.co.uk/dp/B0C7257ZFD
You have to cut and solder the cable much shorter which can be easier said than done if you've got my basic level of soldering skills but I did manage it so if you want to give it a try do so!
The author remixed this model.