Copper Braid Products
 

If you are interested in making your own screened/shielded cables, I can recommend this aptly named company, who are happy to supply their products direct to the public.

The web site, https://www.copperbraid.co.uk/, is easy to use, and the braid is reasonably priced - as are delivery costs.

I used the 5mm tinned copper sleeving braid (4mm min, 6mm max diameter) to construct five-core power cables (2 x twisted pairs: heaters +/-, HT/earth lift, and single chassis/ground - screen braid connected to chassis at PSU end only), between PSU and Pre/Phono.

The braid is good quality, and a professional looking finish can be achieved by covering it with clear heat shrink when you have constructed the cable. As a bonus, the braid is supplied on a flexible nylon former, which can be used after extraction to bundle wire runs inside future projects.