You can get the 70 from places like Droknars Forge and Marhaans Grotto...at least I think it's 70.
Basically the same sets except buying from Droknars can cost as little as 6k altogether if you trade for materials with players, whilst the armour at Marhaans is 15k per piece, and has slight changes in looks. I believe they're the same stats, so there's no real point in Marhaans.
Then again they may have changed everything. I haven't been to Marhaans for over a month.
Where are you up to in the game?
EDIT: 'Tis 70:
http://www.guild-hall.net/craftindex.php
Choose your profession and scroll down to the bottom sets. For example if it's Necromancer scroll to the bottom of Necrotic and Tormentors sets and you'll see they are 70 armour.
EDIT 2: It actually varies with profession. The max for:
- Elementalist = 60
- Mesmer = 60
- Monk = 65
- Necromancer = 70
- Ranger = 70
- Warrior = 80
That's excluding all the little extra items that aren't a full suit. So, bad luck if you're an Ele or Mes...
Then again, the thread is about N/Me build so you're obviously a N/Me.