Sorry to necropost, but just an update of what I've done so far.
Luckily I found a modem PCI card lying around, and also found the drivers for it. So I have this phone line splitter hooked at the cable modem, with one going to the phone out in the living room (that's connected to the printer), and the other is going to the modem that I just installed in my rig.
Fax is received fine, but the problem is, when the fax is multiple paged, I can only view the first page of the fax. I tried looking for an option to show me all the pages, but couldn't see any.