I've just got a spare wheel kit from a Mazda dealer for £244.95 which is around £100 cheaper than any other dealer I have asked. It's a 16 inch wheel, tyre size 145/90 16,but the dealer and Mazda have confirmed that using it will not harm the vehicle in any way if used as recommended. Please note and this is something I did not know, ONLY USE A SPACE SAVER SPARE WHEEL ON THE REAR AXLE. Thinking about it, it's common sense, it just never occurred to me as I have always had full size spare wheels. I have attached ( I hope) a photo of the relevant part of the receipt for the kit.
[attachment deleted by admin]