If you wanna print it yourself, the model is here: https://www.printables.com/model/1348194-4n-threaded-flat-head-screws-and-nuts-10-32-equiva
Design to be a drop in replacement for 10-32 screws with a much, much higher pitch. These screws are extremely easy to print, is reliable enough that it can hold some weight.
If you wanna print this yourself, you need to make sure that the screw is sideways, so if it breaks it’s no on the layer lines.
Using them in my own prints which had metal screws and they are holding quiet well.
Still testing the head designs. Should consider a slot instead since the hole doesn’t take well to a metal screw driver.
As for the fills. Wall thickness has more impact than infill due to it’s size. With that said, from my testing with stylus, 100% infill bends better than 25% which I am using. But as this is not suppose to be used crooked it shouldn’t make too much of a difference.