Hi BODIMEAM
There is a space saver wheel available although not listed in the accessories catalogue.
Just make sure the wheel actually includes the tyre, fixing bolt and tool kit.
When I bought a Seat Leon there was no option to order a space saver at the time. The dealer quoted me just over £200 as an accessory so ordered it. When it arrived it was just the wheel. He wanted another £250 for the bolt, tyre and tool kit, total £450.
Went onto the web, think it was Oponeo tyres. Bought a steel wheel with tyre (not a space saver, what they classed as "temp" since although it was a proper tyre it was a different size (correct diameter - way better than a space saver) for £70 delivered, a jack form Halfords for about £15, a socket wrench out of the garage did the job of the wheel brace and a local engineering shop provided the bits to make a hold down bolt (used the wheel brace to tighten down) for a few pounds, all in less than £90. On that car it fitted under the floor with no boot instrusion despite being wider than a bike tyre.