I've been looking into this recently after talking about then with another guitarist friend.
Apparently, they had to stop selling them in US due to a patent infringement. That patent has now expired.
I'm told the ban only applied to the US anyway, so here in the UK I could have bought one of these any time. Don't know if that's actually true or not.
Wilkinson have a reverb page and you can definitely buy a convversion kit for the vs100n on there. Here it is:
https://reverb.com/item/35360438-wilkinson-vs100n-cv-assembly-conversion-kit-chrome