Personally I just got a pair of 880 600 ohms myself, also in europe. I went with the Zen DAC/CAN stack. I don’t really have anything to compare to and I’m not an audiophile but the combo sounds fine to me. That said, I did modify the headphone to change the cable and use them in balanced mode. As far as I understood that gives them a little more juice than you would normally get.
Going by Amazon or even the Ifi reseller WOD Audio if in Germany you can probably fit both the amp/dac and headphones into your budget. In my case I added a cheap tube pre-amp as well, which only made a minor change but made the sound a little less aggressive and easier to listen to.
That said WaveTheory has put out a recent review here on the CAN that might make you reconsider the AMP at least: 🔷 iFi ZEN CAN Headphone Amplifier