Rocket Stove for Drying Fruit in Guatemala

I am looking for suggestions for how to make a rocket stove/heater for a small concrete fruit drying room here in Guatemala.  I'm hoping to burn sticks and then bamboo down the road.  I would like to have a vertical feed so that I can put in some long sticks of fuel and then leave for an hour or more at a time.  I think I can get fire brick here, but there aren't too many high tech materials available such as high temperature insulation.

I suggest checking out this thread as they seem to want to do something similar: https://permies.com/t/58088/Rocket-Mass-Wood-Dryer-Ecoquest

Also, can you get perlite? I'm pretty sure I've seen perlite-cob mix as insulation.

Our church just sent a missionary team to Guatemala where they build (5) rocket stoves for the poorest inhabitants there. I am not sure what the exact design was, but they said each stove had to be custom built, and that they took photos of the general blueprint on their phones, then built off those photos. I am assuming it would dry fruit as well.

I'll talk to the Missionary Team Leader as her daughter is there full-time as a missionary doing that sort of work.

A long feed tube often causes the fire to burn in the wrong direction,creeping up the fuel instead of burning sideways.
Using a batch box rocket could work. They burn all of the fuel in their firebox over the course of 45(?)or si minutes,giving one time between refueling.
Donkey of donkeys rocket stove forum,has built them entirely of cob.
Sawdust,grain hulls,etc,can take the place of manufactured insulation.
The most basic L rocket, can be used to fire a kiln.
What ever you go with, heating a mass and using that heat over time can keep you from having to tend the dryer.

Thyri- Thanks for the link.  Also, I'm not sure about perlite.  I've never seen it yet, and I can only imagine it's a little hard to come by.  Maybe I could get it in the capital city, but that would be maybe 7 hours away.

Travis- I would be curious to see their work.  Do you know what part of Guatemala they are in?