Terve, Harrin! I bought a Tsekoa kit from Model Slipway in 2007 or 8 when I was living in Elimäki (near Kouvola) but life got in the way and it was sold to a friend (Seppo Hähl) who lived nearby when I moved back to the UK after 16 years of living in kaunis Suomi.
My interest in the Tsekoa still continues, and I bought one from someone on the south coast of England 2 or 3 years ago. It looked well made, but had been well used. I was able to contact the original builder, and it turned out to be David Metcalf of Model Slipway, so I need to tread very carefully with my restoration.
I will be following your build with interest.