I didn't like the rod holders I found, so (as is often the case) I made my own. The STL here is for a 1.5 inch rod. My apologies; I forgot to switch to mm before exporting the STL.
I designed this to be completely parametric in Fusion 360, and included the f3d file so you can adjust the rod size. Just open the file, in the tool bar click Modify->Change Parameters. In the window that pops up you can change the User Parameter "rod_diameter" to whatever diameter you like. It should work down to a 1 inch, or so, rod.
Printed with PETg. Even at 50% infill this thing feels insanely strong. I haven't tested how much weight it will hold, but I suspect the drywall will give up before this thing if you print it like I did.
The holes are designed to accept drywall screws. I suggest using plastic drywall anchors if there is no stud behind any given hole.