Here is the required bit for full floor support - 1st photo - from India with steel wheel. 2nd photo - top of floor support as received, 3rd photo - adapted for tow bar in UK, 4th phot - part number.
If carrying an alloy 16" wheel a little adjustment of the pads on bottom of the support is required, but looks mush better than some made up versions - though some MDF DIY's elsewhere very good