のに is originally an adversative conjunction, as you might know, but it's used to show the speaker's unrealizable wish, similar to the subjunctive past "I wish I/it could ~" in English. You can think that the clause following のに is omitted; such like 届いたりしたらいいのになぜ届かないんだろう/実際届くことはないんだろうな.
Yes for たり. It adds the meaning "or something".