After spending two days looking for these poles, I created a prefab bundle of high tension poles that you can use in Giants Editor to add to your map and avoid wasting as much time as I did.
There are ten distinct kinds of high-poles in this collection, and the poles are taken from many European maps.
If you are unfamiliar with Giants Editor, the instructions may be found in the mod folder's READ-ME section.
THIS IS A PREFAB, AND THEY MUST BE PLACED IN THE GIANTS EDITOR! IS NOT A MOD!
These should assist you with your map modifying, I hope. 😉

Thanks to Andy1