Looking for Boat and advice for someone new to the class

Hello,

Thanks for accepting me in the group!
I am a long time windsurfer and recently started to do some research about sailing. I am interested in the 49er class and the i14. I found a couple of 49ers and 29ers but no luck finding any i14 class boats. do you guys have any idea where I could look for them? i tried Facebook marketplace and craigslist.
What's the price range for a decent boat? is it possible to find something in the 1000-3000 price range in ok shape not too old?
i saw that newer boats have side wings that let you put more weight on the sail and hold more power, is that something that could be added to an older boat? same with the rig, could i upgrade and older rig for something newer? hopefully i can find something that doesn't need a lot of upgrades but just trying have an idea of what could be upgraded.
I am located in Long Island NY but also travel a lot to Miami in case that helps.

Thanks! really appreciate all the feedback I can get.
Cristian