I don't even think it's as many as fifty - even when you take into account the footprint pegs. If memory serves, it's about 6/8 pegs per bedroom and 4/6 for the centre dome.
If you went for fifty - I'd say you'd have spares.
EDIT:
In fact, I have a suggestion. Go to a retail outlet (not online) and buy packets of 10. Only open what you need when erecting the tent and you can return the other (unopened) packs within 28 days of purchasing them.
If you look at some of the members photographs here you may be able to work out roughly how many you will need. I would go for rock pegs but that's just personal choice.
Don't forget to leave a review of all tents you've used, for a chance to win fantastic prizes