First tip for you is to take the Psych GRE. I didn't take it, but it's a must for your situation, to display your psychology knowledge. Your GRE scores are better than mine, but I didn't go for top programs or clinical, so maybe retake the general if you can. Maybe you could try to put together a psychology writing sample, such as a review paper. Attend psychology conferences and network - jot down any memberships on your CV. Psychology and economics are closely related and I don't even think people would think this jump is very unusual!