Generally speaking, diesel oil changes, especially for European makes, will be very expensive. To being with, diesel engine oil is normally required to be synthetic, and formulated diffrerently from a gasoline engine oil. Add to these factors that make the oil expensive the fact that most Euro makes have a proprietary specification, and the oil becomes even harder (and more expensive) to source. Add dealer labour to that, and it's time to bend over.
When I had my TDI Golf, my oil change costs were not outrageous, as I did it myself, sourcing the correct oil at a reasonable price, and sourcing OE grade filters also at a reasonable. I supply my own labour by doing it myself. And I know the job is done properly, and not by a high school drop out who really doesn't care what he's doing (yes, even dealerships hire these guys as they save their certified mechanics for more profitable work). This is very easy maintenance every vehicle owner can and should do.
If you have no interest, at least get the oil and filter yourself, and find a good independent mechanic and pay him for just the labour.