My dealer has supplied just the space saver as an aftersales originally at £75, but then included it as part of the agreed discounted price.
I have the lower boot floor, cargo net etc option ( this can hold it in place ) when I have it in the car. It also has the can of sticky stuff.
Tell the dealer most of what you want, then agree to deal subject to this, then that and so on. The when ready to sign, ask for something else.