What wire to use for a scratch built harness

I'm not restoring or building a stock truck but would like to have a stock (ish) harness to start from. I remember reading years ago that the wire that was used on our trucks is no longer available so I'm wondering what wire are people using in it's place?

Being an electrician by trade, I would like to know the actual wire nomenclature so I can call a local electrical supply house to see if I can purchase it locally. What I have found leads me to believe I am looking for GXL or XLPE wire insulation. It is supposed to be very flexible and temperature resistant for automotive use.

Does this seem right?

try wire care i have a complete harms

Did wire care build you a complete harness?

I believe it had tin plated copper wire and silicone jacket in 14 gauge made by Prestolite

i pulled it out of my truck when i rewired it.