Going on whats in parts catalogue...
That's for the fuel return pipe.
Diesel: NRC9678 (but mircocat says it's NRC9562 which might be wrong)
PETROL: NRC9678
GASKET: ESR3277
The petrol one doesn't reach half as much into the tank as the diesel one, for whatever reason that maybe.
You'll need the screw fixings also...
BOLT: 3890 (2 off)
LOCK WASHER: 3101 (2off)
You can get all these parts from
www.beamends-lrspares.co.uk for under £15.00