update: I had it done - by a mechanic of my choice. The problem with the workshops that have the pressing tool (like in that one YouTube video floating around) was that they were all afraid it would be stuck too tightly and would take longer than expected, because the tool might fail. So, the estimate was: it could take 1 hour, but it could also take 4 hours - which meant the price for just the replacement could range from 65 to 300.
The mechanic didn't have the right tools and it took him a long time to remove the parts. Also, this was the first time he had worked on a Golf 4. It took 8 minutes to press the parts in. I just received some helpful tips here, thank you. For next time...