If you apply this time, you will guarantee there will be a second time.
As someone who is turning 29 this year (and many others around here who applied in their late 20s or 30s): don't waste your time and money applying now. There is time later.
Investigate DO grade replacement and put your money towards that. You could turn yourself into an interesting candidate, but your current academic record makes you too risky. Just for perspective, I had a steady 3.5, and 513 and got shut out. There are a lot of very qualified folks applying...