Tickets are still available: you register and print out your tickets at the Opera web site.
I won't be there. I was supposed to see the Symphony, which is performing the Magnus Lindberg commission, Seht die Sonne, yesterday. I should have checked the schedule, because the performance was a rare Thursday matinee, which I discovered around 5 p.m., long after the concert was over. I'll be at the Symphony tonight, and will catch Lucia another time, or not at all.