A few other things to consider:
Wand of Mage Armor (750 gp): With a one hour duration per casting, this will last for quite sometime. Also, if it gets dispelled, it is easy to replace. While not as good as the greater version, it does not take a valuable 3rd level spell spot and is much cheaper than the equivalent Bracers fo Armor +4 (16000 gp)
Rod of Metamagic, Lesser Extend (3000 gp): This can greatly extend the use of the shield spell. At 8th level, this should last 16 minutes. With two castings, you can get a half-hour out them. The various ability enhancement spells (e.g. Cat's Grace) can also be extended. Consider getting two rods.
Magic Circle against Evil (3rd level spell): Takes up a 3rd level slot, but provides multiple benefits and has a long duration (10 min/lvl). The deflection bonus can replace the expensive ring of protection in most cases and it provides a benefit to saves, protection from summoned monsters, and charming. Also, the 10-ft range emanation can protect teammates. At some point, the fighter will thank you for this
