Why do people say this? Its so stupid, who cares if someone wants to get right into park skiing before learning to ski first? This is freeskiing, not some racing training camp, do what you want on the hill.
First off, skis-
OP, tell us a bit about your skiing ability. I'm guessing you will be a beginner in the park, and will most likely not want to be limited to one aspect of skiing since you haven't really tried out the sport yet, so I would say look at basicelly any companies mid-level/entry park ski. You are pretty light and just starting out, so you most likely won't be beating up your gear too bad, and lots of those skis will ride out of the park just fine too.
Examples:
Line Mastermind
K2 Press or Sight
Armada El Rey
etc, etc, pretty much every company out there makes a ski that would fit your needs. You are just starting, so don't worry too much about the little specifics about your ski choice, that matters more when you are an advanced skier and know exactly what you want/are very hard on your gear.
Boots-
One thing you should know about freeskiing, is that unlike snowboarding, boots can be a real pain in the neck. Shin bang, foot cramps, etc. are really easy problems to develop, especially before you learn good skiing technique, and thats why its very important to put both the money and the time into getting fitted with a proper boot. You don't need a freeskiing specific boot, just having a boot that fits you is what is important, even if its off the used rack. *HAVING A PROPER FITTING BOOT IS THE MOST IMPORTANT PART OF YOUR SETUP*
Bindings-
Again, seeing as you are light and just starting out, you won't need anything too crazy for bindings. Ideally, you want a binding where your DIN will be in the middle of the bindings DIN range. So for you, a 12 din binding will most likely suit your needs.