i did try looking for a coil burner a while ago, had one at uni and it was realy good at heating up naturals. however couldnt find one, but now i dont even need one at all.
I have a gas stove at home and what i did was find a really fine steel mesh. it was really fine mesh used to cover pans when adding stuff so the oil dont go everywhere.
i put the fine mesh over the gas stove, and then put the coals on top of it. the coals are directly above where the flame touches the metal mesh. the mesh gets red hot and i put the coals (cocobricos/coconaras) a couple of minutes each side.
heats them quicker than the coil burner as i beleive you get sort of the same coil burner effect as well as the extra heat from the flame. i have no need for a coil burner now