It might be a good idea to print a first version with no infill, just to check for dimensions before going for the definitive part. Adjust the variables in the openscad file and regenerate a stl file until it fit.
I suggest printing in ABS as it can flex more than PLA before breaking, but that's up to you.
If using ABS you could also dip the part quickly into acetone and let it dry for a couple of days, to reinforce layer adhesion and strengthen the object.
I also recommend printing the parts rotated 90° (on their side), using support, as the first one printed straight up broke in the same place due to layers detaching.
Use V2. Seriously, it needs less plastic and won't break as easily because the forces are now all vertically aligned.
Hanno reported the version without reinforcements fits better.