I recently bought the Mitsubishi bootliner made for the Outlander from the local dealer. A bit pricey (about 80 Eur in Sweden) but good quality and obviously fits perfectly. Even has a Mitsubishi logo molded on it for the fashion concious.
I bought mine for £18 from seller = jvlhomewaresolutions on ebay UK. Not sure if they still have some or if I'm allowed to mention them like this but I was very impressed