I seem to recall a Magic Item Compendium item - possibly even a relic of Pelor - that helped with turning checks. Let's see...
Ah, there it is - Scepter of the Netherworld. Definitely not a relic of Pelor. Allows you to turn or rebuke undead as though your caster level were three higher than it actually is. Costs 9,000 gp.
The way that's worded, I don't think you could manage to make it stack with the Phylactery of Undead Turning, so it's probably only of use to you if your Head slot is occupied.
You may also want to check out the Reliquary Holy Symbol - no boost to caster level, but it grants extra Turn attempts per day.