Although the vendor says its a 2014 to 2018 I would email him with your 4 hole pitch size to ensure that it will fit on your Ecosport, before buying it.
Even if you alloy wheels on your car are 16" or 17", a 15" spacesaver is ok as the rolling radius can legally be slightly different on a spacesaver, which it will be.
Conditions of use for spacesaver, max speed 40 MPH and replace it ASAP as soon as you get to garage or home.
Also ensure you get a 2 Ton capacity jack for the Ecosport around £20 for a good one, and an extending handle brace around £7, and two chocks to brace diagonal wheels on a slope to prevent slip (a fiver for the pair, usually steel, or wood or plastic)
I got me a spare wheel from ebay but am struggling to find a jack, got a workshop one at home but thats to big to carry round, any suggestions as to a suitable scissor jack? there are lots out there but with different sill fittings???????? a picture of a genine one from an ecosport with a spare wheel would be great.