You can take the switch apart quite easily so you could presumably take the actual switch out of a rear one and put it into the larger trim of the front passenger one.
I'd thought something along the same lines, but didn't want to say anything till I'd actually checked it out.
If you need a new switch, ie. something's broken (and it's not the surround) then I can probably get a rear-window switch to you. I'll see how easy it is to pop-out ..... pretty easy I think cos I remember taking the whole panel out of the driver's side for something
Knock a quid off for the surround