You could get the 1415 motor from castle if you like brand matching (me LOL) but the tenshock seems the best value is your blitz 2WD or 4X4 I know nothing about SC and for a heavy vehicle like an SC you definitely want a 4 pole check out Jang's reviews at Ultimate rc.com under other stuff-reviews hope this helps PS how is the Mamba max ESC? Thinking of buying one with a 1406 7700 for my 2WD buggy does it run hot?
Edit somewhere around 3500-5000 have you looked at the Traxxas VXL motor with 3500kv that thing seems to cart around the slash pretty good up to 60-70 if I'm correct personally I prefer High KV but lower kv has more torque if I'm right?