Two old spread-eagled 5/8 wrenches and an old cup.
Welded by a blind person
A nut and bolt and a few flat washers
For most of the 20th century British made bikes used the 5/8 raised slot on the fixed side. The adjustable side less so but mainly dowel holes, if not the same. Hundreds of millions of bikes used this setup.
The shipping to the UK for the featured tool doubles the price but it is a heavy item.