Prototype printed with PLA, 1mm top and bottom shells, 5 perimeters, this makes the U shaped part of the holder sturdy enough. Slides onto 17.5mm headboard, dimensions can be adjusted in the source files or just drop me a message with specific thickness.
Sources available at https://github.com/ceresek/prints/tree/main/things/holder-soundmaster-radio.
The author marked this model as their own original creation.