I just found the rod, but I need more than 2 screws, since the curtains are heavy, and at least 3 brackets across the 42 inches are a minimum, judging by the other curtain rods which are installed.
I guess I'll come across the screws, since I probably placed them, "where I couldn't miss them", like the rod.
The rod was near my computer, so it was easy to find.
I have everything assembled on a makeshift drafting board which I've used for various things: sorting, drafting...