I rebuilt the source from the ground up, adding in some attractive fillets and most importantly altering the geometry in the upright so that it should be printable without support! An ~8mm bridge should be no trouble for even a moderately out of tune printer :)

I would recommend 3 walls and 12-18% gyroid infill for stiffness and strength. PLA should be more than fine unless you intend to leave this in a non-climate-controlled shop in the summer.