Naw, I'm a cleric. Divine Metamagicing Persistent every day would burn up most of my turn attempts. . . though I suppose I could see if the DM is going to allow custom magic items, just get something like that.
Or just ask to treat your fist as a natural weapon. It's natural. It's as much a part of your body as a fang. If you've got Improved Unarmed Strike, you can use it as well as if it were a weapon. I think it'd be harder to justify it not counting as a natural weapon.
That is incorrect, divine metamagic lets you lower the cost of a metamagic by burning turn attempts. Get the magic item that has charges of turn undead (night stick I believe) and/or extra turning and bam cheap metamagic buffs all day.