The 'keyboard end' card installed towards the front left side of the computer? I vaugly remember that discription on some 80-column cards at any rate. Probably the best place to find a card is to ask on comp.sys.apple2.marketplace.
If you don't have a Super Serial, but do have a working DOS 3.3 disk for your apple - doesn't have to be a system master, just any disk that boots DOS 3.3. If necessary, press RESET before any application starts running, after DOS itself has been loaded.
And if you can solder a custom cable, which will go from your PC's parallel port to the Apple's internal or external joystick port.
Then you can use the program "ap2222pc" to transfer 5.25" disk images (usual file name extension .dsk) to and from real Apple disks. It isn't as comfortable as ADT and also a bit slower, though. You should find it on the net. The included documentation explains everything.
-- Linards Ticmanis The Master said, "The business of laying on the colors follows the preparation of the plain ground."