I appreciate the reply. I have already ordered a replacement WiFi card for the laptop of the same brand/model that is already in the laptop (Intel centrino advanced-N 6230), so hopefully replacing it with the same physical device will not cause a problem. I think it's a shame that Sony needlessly prevents it's customers from upgrading their peripherals (or even simply updating drivers), but I'm assuming replacing a failing peripheral with another of the same will work. I will post back if it does not.
Cheers!