Help - Water Hose And Piping C34

[wagon]

Has anyone had issues with corroded water pipes?

Having some trouble finding replacement parts. Main issue is this part

http://www.sau.com.au/forums/topic/406178-need-to-identify-and-replace-this-coolant-pipe/?p=7714417

Which if the other thread is correct, doesn't appear to be on the WC34 Water Hose and piping diagram, attached.

The mechanic also wants to upgrade a few other bits whilst this is happening but not sure of part no's.

x1 Metal pipe connection

x2 Plastic fittings

x1 Inlet Gasket

x1 Plenum Gasket

Also the 14875P and is the top left circled part 14875PB?

Any help appreciated.

Thanks