Oil cooler woes

[johnny_quattro]

I have what I suspect is a leak from the oil cooler on my 4.2 A8L facelift model, 2000. Checked the oil (as I do every fortnight or so) and was alarmed to see so little oil on the dipstick. Looked underneath and I could see oily parts on the plastic undertray.

Could someone take a look at the attached photos and offer any advice, in particular with regard to not only why these things break but also that oil cooler coolant pipe made out of plastic? I don't think mine is broken as the overflow container is just full of the red coloured antifreeze mixture and is certainly not that chocolate brown emulsion thing.

What is more likely - is it the seal/gasket that's gone or is the whole unit going to be needing replacement? I have already ordered one of the those replacement aluminium parts that is referred to in many posts on this forum. My thought process being, if the oil cooler is indeed shot, then it would need to be replaced but I wouldn't want a new part installed with the same old plastic coolant pipe being put back in.

I'm somewhat clueless on this so I've already warned the garage of the silver QE2's imminent arrival. Any ideas on roughly how much labour would be nice to know.

Cheers all, happy New Year to you all.