For all those, waiting for the update:
I'll still take some days. The valve seats are beyond re-grinding and need to be replaced. One shop quoted 160€ per head, plus shipping and material. The local shop anyhow was somewhere around 40€ per seat, plus material, and is only 15 minutes away. but it's gonna take some time, as usual.
Also, the paintjob has to be redone, as it seems to have gotten too much of the cold, and the paint didn't bond with the primer - bad luck. So I'll be taking all the parts back this weekend.
Yet another round to be taken