I decided that a DIN-mounted power supply will be a good addition to my RackPi and I've designed one. I'm attaching a “single unit” model and “double unit”, any size can be made just by scaling or duplicating the ”single unit" one.
This is a simple model that works with DAP Empty 2U Rack Panel (https://www.dv247.com/en_GB/GBP/DAP-2-HE-Rackblende-f-Modulsystem-10-Segmente-MP-1/art-PAH0017160-000) but I think it should also work with a rack https://www.printables.com/pl/model/206043-rackpi-hd-higher-density-2u although I haven't tested it.
I've printed the prototype in HD PLA, but I'm going to print it in ASA, although the prototype works fine. Print without supports
Edit 20230424: I've re-uploaded both models with fixed dimensions, DIN rail was not wide enough.
The author marked this model as their own original creation.