From memory of my 2002 car there was a heat shield protecting the brake reservoir. It was insulation stuck onto metal. Fairly sure it was aluminium. A straight forward fabrication job. You can get suitable Al sheet off ebay. 1mm thick is easy to cut and form then stick insulation on the side towards the fluid reservoir.
It was on the car when I bought it.
If you buy some textured sheet then get enough to make shields for your cats as well. I did this and used stainless "cable ties" to fix them on.
