Dire Charge? Yes, I suppose I'll allow it once you hit epic.
EDIT: I forgot to point out that, Rules As Written, I believe it is explicitly spelled out that you can use a magic item that grants a constant bonus to an ability score to satisfy a feat prerequisite. Of course, should that item be suppressed by dispel magic, lost, stolen, destroyed, or if you find yourself in an antimagic field or in similar straights, you will not be able to use the feats until the item's power returns/you recover the item. I will note that, as a 15th HD character, you do have 3 ability score bonuses to spend, so hypothetically, a Dex 14 before racial modifiers would be sufficient to get you to the 17/13 you need.