Hi ndnguy,
Given what you've described about your goals and timeline, you could certainly hit your score goal in the time allotted. Based on your Official GMAT score, you don't have to purchase the ESR though (your Scaled Scores show that you lost LOTS of points in all of the major categories). Before I can offer any pointed advice, I'd like to know more about how you've studied so far:
1) How long have you studied?
2) What materials have you used?
3) How have you scored on each of your practice CATs (including the Quant and Verbal Scaled Scores)?
4) Did you take the ENTIRE CAT each time (including the Essay and IR sections)?
Thankfully, the GMAT is a predictable, standardized Test, so you CAN train to score at a higher level. You'll have to make some adjustments to how you 'see' (and respond to) the Test though.
GMAT assassins aren't born, they're made,
Rich