Would this work? I looked it up and the chipset appears to be RT2860, which ralink has drivers for mac 10.3/4/5 . It is b/g/n-draft compatible and supports wpa and wpa2.

"An empty PCMCIA type II slot (CardBus Compatible)" is the only thing, as I'm not sure the exact slot on a wallstreet. I recall hearing the "wallstreet and up" are cardbus compatible, but I want to make sure.

If this will work, I think it is exactly what I am looking for.