Just in case anyone else gets stuck to buy lambda sensors for subject engine here are the part numbers:
Pre Cat Sensor:New part no. 93189974 ..Same as old part no. 23527304
Downpipe Sensor: New part no.93189975..Same as old part no. 25335280.
My engine has two sensors and it's a 2002 model.
The info in the MK4 info files forum is slightly incorrect for this engine.