I’m very sorry for your loss. This is always a difficult decision to make, because you never know if the bird will accept another cockatiel. If he is tame with you, and you can handle him daily after work, then it might be best not to try to get another one. If he is not tame at all, then it would be good for him to have a companion. I would try to find another male around his age, and then you need to introduce them very slowly. Start by having the cages near each other, and gradually have them side by side, watching for any interest or aggression. Once they seem to get along, you can start with some supervised interaction. But if they do not get along, never try to force them. Some birds simply don’t get along, and you won’t know until you try.
Thank you for asking Lafeber,