^ this. Run line in on one of the recorders you list in your sig.
One of them likely can output usb, and act as a sound card.
But, I'd recommend a different workflow, based on prior experience.
Just record the line in input, then upload the file to your mac later.
Tape head alignment and pitch correction likely more important than most everything digital.
Even on modern macs, system scheduling issues can mean that your usb input to buffer process can get screwed up without an overt sign.
Running tape deck > recorder is super simple and rock solid.
Nice to be able to import and track whenever you have time, and simultaneously just churn through your pile of cassettes any time you walk by, day and night, until it's done.
Finally, a bit of research on which of those older shows are available to torrent or whatever can save a ton of time and energy. Tracking 1200 cassettes will take forever.
Have fun!