I recommend not buying any shire armor(left side) at all. Use your tomes on a shire weapon and shire right side pieces ie the jewelry. You get a box of free left side gear which is 200ilvl including a belt by finishing the 60 class quest. The reason is that you will replace your entire left side by running just five dungeons. You are given one piece of visible armor per run and this piece isn't a duplicate of anything you have. Starting at 61 in Siren's this will be ilvl 260.(?)
As a white mage, you will want to hit your level's dungeon a couple of times to keep your level in line with your main story quest so this all works itself out.