I dunno about him, but I do something similar on one of my machines. I use an SCM SPR-532 USB reader with pinpad and an OpenPGP v2 smart card. More info and pictures here - https://grepular.com/Smart_Cards_and_SSH_Authentication
Where did you get the PGP card? Did you donate to become a fellow?
I've been thinking about it, but it's a bit confusing figuring out what cards are compatible and donating to the foundation is nice but a bit expensive.
I got it from kernelconcepts as tokenizerrr said. They seem to have a newer version of the card now which does 4096, so I might have to buy another. Mine only does 2048
