Pellet Extruder

I am at the moment implementing a ECO-FAB-LAB in the university in Chili-Southamerica to teach both resycling and printing with a robot-arm.
I need support if there is any better option than the Mahor-Printhead which is payable.
I expext that hera are a lot of cracks on this area-thats yust what I need
Thaks for answers and experience