Coupling change Material costs 2000 Euro?

Hello community, in advance, I have little idea of cars. I live in Mallorca and have also bought a “domestic” Opel Frontera DTI 16V (RS) with 85 KW, 3 Türer Sport, built on 20.7.1999. Now the clutch is due. My workshop thinks to me that the spare parts alone would cost about 2000 Euro. Did I tell me something (I didn’t really understand) that you have to change not only the gearbox, but also a part between the engine and transmission. demand help? Bzw. where can I buy the required spare parts in D?