Assuming that you havn't already maxed out your studying, its very possible. I increased my score by 140 points in 70 days from a 570 (with no studying) to 710. The good news for you is that your quant is low and verbal is high. Verbal will help drive your overall score, and Quant is definitely easier to learn then verbal. So concentrate your studies in quant, while learning verbal (to increase that score even higher) and I definitely do not think a 750 is out of reach. Its up to you though to put those hours in. I studied for about 200 hours, so I would recommend atleast 100-200+ for anyone trying to greatly increase their score or reach the 99th%. 12 weeks - 15 hours studying per week - 180 hours of studying
Search around the forums for other success stories, and pick up the best study material around.
Good luck!