A Worthing-based dealer is offering some front and rear mud flaps on eBay.
http://www.ebay.co.uk/itm/NEW-VW-UP-PAIR-FRONT-MUD-FLAPS-1S0075111-/130716675177?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item1e6f522c69#ht_558wt_1398
http://www.ebay.co.uk/itm/NEW-VW-UP-PAIR-REAR-MUD-FLAPS-1S0075101-/140779787921?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item20c7211691#ht_558wt_1398
Nick
http://www.ebay.co.uk/itm/NEW-VW-UP-PAIR-FRONT-MUD-FLAPS-1S0075111-/130716675177?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item1e6f522c69#ht_558wt_1398
http://www.ebay.co.uk/itm/NEW-VW-UP-PAIR-REAR-MUD-FLAPS-1S0075101-/140779787921?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item20c7211691#ht_558wt_1398
Nick