I loved the Bethancourt mallets. By the end, I had about 5 or 6 different set gradations, even though they were only marketed as "Andante" and "Scherzo". Unfortunately, the raw gum rubber degraded over time, so they all died, except for one set that I wrapped with yarn. and even those have changed from soft to hard.
You are right: no one is making anything close to the Bethancourt mallets.