It is a private brand; the label inside says Made in China. He (Matt at WOU) designed a very limited run of Concert and Tenor Ukes, and when they arrived they had included a few Sopranos as samples too (except they had charged him!) - this is from what he says on his website:
"One thing I also wanted with the World of Ukes Pioneer 1T was to use a small workshop, rather than one of the giant factories. This was definitely not a badging-up exercise – no, I wanted very much to make a low production run, bespoke model to my specifications. To that end I used a small workshop with a lot of passion and skill, which worked by hand as much as possible. So, the build quality is good but the gloss finish, if you hold the uke to the light, has miniscule imperfections caused through being sprayed by hand, rather than machine. To me, given they look lovely and you can’t see this unless you are inspecting with a magnifying glass, there’s no issue – but I thought I’d mention it, and the reason why."