Heat diffuser for cazuela?

[danysedai]

I'm in Edmonton, but if you don't live here and know a general store where I can find a heat diffuser to use with my electric stove, I'd appreciate it.
I've bought some clay spanish cazuelas, and I've been reading on how to use them on the stove and it was recommended the use of a heat diffuser. I haven't seen one in the stores I usually go to. Anyone can help,please?