Not knowing where you surf, what you want out of your board, your fitness level, your surfing style, what you've been riding, etc... it's hard to give you any advice. Off the top of my head, at your size, if you're an intermediate, I'd say 6'6x12x19.5x14.5x2.5 typical single to double concave, thruster setup. Look for something used. You can find a decent board for about half that if you look hard enough.
