There are a few aftermarket ones on the bay, but i have read that they need work to fit properly, ie some fixing holes do not line up etc,
https://www.ebay.co.uk/itm/322858706...3ABFBMnpGylsdf
Might be best to contact Mickyboy to see if the can sort you out a good used one.
Copied from another thread.
They all had different Undertrays
but now only one is available and listed for ALL Models (except 1.8)
Part No: KRB000380 Undertray-engine bay sound deadening £114.74 + VAT
The Diesel one to Serial No:263238 was KRB101050
The Diesel one to Serial No: 321637 was KRB000220
The Diesel one from Serial No:321638 was: KRB000390
The V6 one to Serial No: 263238 was: KRB100831
The V6 one to Serial No: 321637 was: KRB000200
The V6 one From Serial No: 321638 was: KRB000380
The 1.8 to Serial No: 269854 was: KRB000200
The 1.8T to Serial No: 278939 was: KRB000340
The 1.8T from Serial No:321638 is KRB000400