Here's one of that start of a whole set of accessories for my Mega Brick Figure

This model is also available on Printables.

Printing

This is a much simpler print than the whole figure or skeleton: Just print everything in the single included 3MF file. (There are 6 pins in the file, which includes 2 extra in case you lose some or they don't print quite right.) There is support material required for the underside of the hat, which is included in the file. Ideally, this would be printed with tree support, but for now it seems that Bambu Studio freezes and crashes when trying to slice the tree supports for this model (though it does work in Prusa Slicer.)

You can print this in PLA or PETG, but I expect that the hat will hold tighter on the head for longer if printed in PETG.

If you have trouble with the pins staying adhered to the bed, try adding a brim to them. If they don't quite fit when you assemble the print, try printing them a few percent smaller.

Assembly

User CA glue (cyanoacrylate/super glue) to glue the pins into the ring. Add glue to the top of the ring and pins, then press into place in the top of the hat.