Ahh I see, obviously don't paint that with hammerite, but you can get a Brembo disc with a painted contact surface too, should be good for your low mileage application.
Otherwise, might be worth giving the brakes a good cooking to remove any rust then once cool cover the wheels so they don't come in contact with any water.. it may stop a bit of the oxidisation process.
Re: Pads, the red box ones you've linked to should be fine if your not using the car to its ability.