One option is to carefully open up the pcmcia card, and look at the tranceiver chip inside. These are normally easy to spot as they are near the connector end.
You should only need to solder 4 pins for it to work. You should be able to get the chips datasheet if its not obvious what the pinout is.
I did this a while ago on some 3com 10 meg ethernet cards which had missing dongles and they worked great!
