This forum thread nicely shows how to refurbish a door wedge power supply:
Forum64 – C64-Netzteil – noch ein weiterer Umbau
Greisi’s power supply:
Starting at 3:40, he nicely explains why using a switch-mode power supply directly from 220V->5V is a bad idea.
Someone has also shared the layout on PCBWay.
I compared the Gerber files on PCBWay with those on Greisi’s website. The ones on PCBWay are even a bit more up to date.