Dreadfully sorry chaps for taking so long to reply, awfully remiss of oneself, I know, but, in defence, I was rather floored by a severe case of gastro-enteritis...
So, actually, in Vulcan 607, the story of the first Black Buck raid, the chap there said 17 aircraft, however, that might be 17 sorties but 13 aircraft (I don't have to it hand), so, Guardsman, over to you!
The bonus questions were:
The Navy speculated on a strike using Sea Harriers, but, whilst that happened latter, for political and morale reasons (and because the RAF felt out of it), an immediate strike was felt to be the best option. As for strategic reasons, well, that's a matter of debate (some say that the Argies never intended to keep their fast jets on Port Stanley). The Sea Harrier is now, of course, out of service (as is the Vulcan).
The RAF also considered using Tornados to carry out the strike, which were just coming into servic. However, whilst it could be refueled enough to strike, the engines would have burned out due to a lack of oil. Ironically, the Tornado, like the Vulcan in 1982, is being cut down, almost in it's twilight years.