Whilst I haven't tried this in a saloon, I can't see why it wouldn't be just as relevant...
I'm currently using the secondary spare wheel hitch point below the rear side window, and so was in need of a decent spare wheel cover that wasn't too 'new' or garish. A Rover P6 spare wheel cover (the one that goes
inside the boot, not the one for the bootlid mounted spare) fits very nicely, is smart looking but also appropriate material (think it's coarse grain vinyl - will have to check later) so fits well with the colour and materials used for the boot trim in the estate. A second hand one will also be much cheaper than the accessory one sold for Amazons.
No piccies at the moment as it was dark when I fitted it last night, but will get some soon! Hope this is useful