I've found these products that go by the name CLEAR BRA or INVISIBLE SHIELD. They go on car's front ends to prevent dings from road rubble when driving. Whatever name the retailers call them, they are all pretty much made by 3M as PAINT PROTECTION polyeurothane supplies. They are usually 8mil. Some are thicker and rated for outdoor use.
Thinking about creating some custom shapes using a CAD program and having them laser cut either from the retailer or from a laser cutter that we use for making architectural models.
8mil should be thick enough, I'd think. and if the cables rub thru, I can make loads of spares and can replace them easily enough.