Where about Minas Gerais are you? (I live here too, just curiosity)
What kind of soil do you have there?
What sort of climate do you have there?
In Minas Gerais the IEF
? (Instituto Estadual de Florestas) could give you the native and also fruit trees for free. In every medium city they have one.
I am just new to permaculture, but I would like to check if I understood what you described. You have 1500 sqm of wooded land (and 1000sqm are due to slope), how big is the area for the horses? Are you going to keep the horses?
What you could do is to use the slope area to plant some native trees that would feed the natural enemies so you wouldn't need to sacrifice so much of your space for planting flower trees in your farming area.