Fortunately there are a few hard core side valve experts. Such as Ger Dijkshoorn from Utrecht. He has seen the story go around. When he started in the HD world all his friends rode 'Liberator'. Because those things were for sale on every street corner for 100 guilder.
In the meantime, the Utrecht Amaliastraat is a kind of mecca for WL enthusiasts. There is even a block from Singapore that needs to be overhauled. In that process, it is almost standard for Ger to bring the WLA and 'C blocks to civilian specifications. That saves around a quarter of power. Ger knows the way in parts of the country as in his pocket. And things that are no longer available, he has them copied.