You're on the light side, but the height of a small monument

so you really will not want to go smaller than 130 look for something in the middle of that range 133 x 41 would suit you well. Look to spend between $500-600 on a good quality second hand 2010 or 2011 board.
Its an ideal time as most cashed up, experienced kiters will be looking at the new gear which is starting to land in shops now.
Look for a 'freeride' board, comfortable with some flex and performance, steer away from anything with a lots of rocker (harder to go upwind) or anything too freestyle orientated (not much flex and too stiff), and if you're committed and will get out a lot, avoid beginner boards because you'll outgrow them too quickly.
There are so many brands and models and everyone has their favourites, but talk to the locals at your spot, whoever is giving you lessons, and your local shop and see what they recommend.