A lot of insulating materials are also non-metallic, which typically don't have a high specific heat. However, I am interested in experimenting with insulators that conduct heat as well as metal, but impede currents just as effectively as typical insulators. Does such a material exist?
Glass for instance can act as an insulating material, but it has a pretty high specific heat. On the other hand, rubber often has a lower specific heat, but it will melt rather easily. Copper has a low specific heat and a high melting point, but, it conducts electricity very well. You can see there is some challenge in figuring this out without explicit experience with such a material.
The temperature range is high, which when you talk about electrical components that can tolerate high heat means it's at least high enough enough to burn your skin. Since I am concerned with melting points in materials like rubber, glass and different metals, the range is least a few hundred degrees (either ºC or ºF) to 2000 degrees, depending on the actual impedance of the material. However, it should be publicly viable for experimentation, the highest possible grade material like diamond is not necessary.