Any gear you get from a pack that you buy at level 58 will be level 50, so you'd be better off waiting until you reach the next gear tier.
Second, the best gear in general is found currently in the Professor's Hoard. When I say 'best in general' I mean, it has fairly decent stats and a strong chance of you getting all the pieces that you need quickly. If you have limited crowns and don't PVP, Professor's Hoard will get you decent gear without you needing to spend a fortune.
Best crowns boots are Ghulture's Hoard.
Best wands are Immortal's Lore (very rare drops) or Terror's Hoard. Both have high critical and high critical block. The Immortal's wands have May-Cast spells at all levels.
Third and finally, once you reach level 60 you should do Waterworks and try to get that gear. With a Waterworks hood and robe, combined with Ghulture's boots and an Immortal wand, you'd have the best gear possible for a level 60 wizard. (For the best ring, amulet and athame at level 60, do the House of Scales or Tower of the Helephant dungeon.)
Alia Misthaven