Government Land Rental / Purchase

Hello,

I am looking to invest in a small plot of land approximately, but no bigger than 50 meters squared in Itatiaia-Rio de Janeiro, specifically on the summit of Pico das Agulhas Negras about 9,000 ft above sea level. I am from the USA and want to purchase a small patch of land there to set up some small weather monitoring devices (they do not use gas or electricity) which monitors humidity.

I can't find any listings of land anywhere near there so I am assuming it is government owned and you need to apply for some sort of special permit or request. I was wondering how I would acquire this lot of land either through purchase or rental and where I would be able to find a real estate agent that can take care of this sort of request.

Thank you very much in advance

Abe
Katbi