Guild Wars 2

I am still unclear, does lvl 70+ rare can still get you Precursor? Or lvl75+. Or it needs lvl80 exo to get it?

You can get them from rares, as for levels. People say different things, but i remember reading it was from 76+

you can try at levels under level 80, but keep in mind the chance of getting a precursor with level 80 rares is around .1% or .001.
Getting an exotic from rares is maybe 20% then that can lead to better chances for a precursor.