The Calamity Salvager *does* re-sell you achievement items after you've received them. You don't get them from the Salvager the FIRST time, but if you misplace the item you can buy it back from them afterwards. That's most of their purpose: to re-sell you a small amount of quest rewards, and the bulk of achievement rewards if you discard them for some reason and want them back.
You receive any and all achievement rewards, the first time, from Jonathas 'Master of the Rolls' (not "The Archivar".. not sure where you're getting that name unless that's his name in another language) at Apkallu Falls.
http://ffxiv.gamerescape.com/w...
If you lose the item or destroy it, you can buy it from the Calamity Salvager. Hence why the black text there sayas "Resold by Calamity Salvager", then lists its name and the gil cost. Go talk to one and select the 'Achievement Rewards (Gear) II' section in the box that pops up, and you'll see it there (assuming you've received this item already from Jonathas)
:)