Ok, so here’s the short story:
As you can read above, I’ve imported such brake assemblies from Korea in the past, but the source was dry since ~ 2021.
Back then, I gave one of these assemblies to a dear friend, owner of a folding bike store (and forgot it).
But my friend retired last year and recently, he handed over a big box with all Strida parts which were left over at his stock.
And to my surprise - I found one brake assembly in that box. 
Thanks to Friso, we have a special thread for such things - please continue here:
https://www.stridaforum.com/t/read-this-first-about-posting-in-the-old-and-rare-parts-mk1-3-category/4690
Thanks 