After much consideration, I decided to purchase a full size alloy wheel & tyre as it was better for me to have a full size wheel & loose some boot space rather than re;y on a space saver wheel which seems to come with minimum actual mileage capacity & speed restriction.
The wheel fitted in the car well but the width of the tyre protruded 4 inches above the well top which means I have lost the bottom layer to the boot. There is plenty of packing space around & inside the wheel for the jack and all other emergency bits & pieces that I like to carry.
The wheel I ended up with, after much deliberation and extensive enquiries, was bought from Pneus Online at a total cost of £126.56 with the tyre fitted to the rim, balanced and delivered within 4 days , all inclusive. This worked out cheaper than the cheapest space saver I found.
For your information my car is 2017 Kadjar Dynamic Nav TCE130 petrol and the products I bought were ;-
ALLOY RIM - IT Alice - 17" 7J - Offset 40 mm. centrerbore 66.1 mm. PCD (Pitch circle diameter) 5 x 114.3 mm.
TYRE - Aoteli - 215/60 R17 96H . This tyre is the same spec as the originals on the car.
The overall service, parts & delivery was excellent but the only problem I encountered was that the wheel brace did not fit in the nut cavity of the wheel which was simply overcome by using a 17mm. socket .
I hope this is useful to the forum and if anyone wants to ask me any more information please don't hesitate to email me as I did spend a long time on my research and are happy to pass on my findings . firstname.lastname@example.org
PS. It proved impossible to get any information from the dealership !