Here you can find heatshrinks and braided sleves ("snake skin") of different sized for DIY cables.
Colored Flexible Polyolefin, 2 to 1 Ratio Heatshrink, different colors
Braided Sleeve for Power Cables, 1/2"=12.7mm, select colour, by 0.5m
10% silver coated OFHCC conductors for ultra low noise and high-speed...
DH-Labs SilverSonic D-750 75 Ohm Coaxial Digital cable, 1.5 meter....
Legato US AC Connector