I was also trying to order by them and I was also confused and finally ordered from eBay the following balanced cable which is around 40 £ and is UK hand made and is fabulous in sound quality and also very good looking.
I am using this cable in balanced mode with my es100 and the sound quality I am getting defies both the law of physics and economics. I am also using this same cable in unbalanced mode with the following adapter with my little bear b4 tube portable amplifier.
What I am sacrificing from the balanced mode I am getting back plenty from the burson audio opamp V5i which I reviewed recently. This opamp transforms the little bear to a potential giant killer and is driven unbalanced again from the es100. Altogether, 53 £ (little bear) + 75£ (es100)+ 40£ (opamp) + 40£ (cable) a very budget friendly package which matches the budget price of he4xx.
I have also tested xDSD with he4xx also a fabulous sound quality but less budget friendly package. At that time though I did not have this balanced cable so I tested in unbalanced mode.
I have also two other balanced cables from the same seller one for my HD6XX and the other for my Meze headphones, roughly same prices and also magnificent sound quality albeit different colours and all 1.5 meters long.