The Puukko is a fantastic field knife, you certainly made a wonderful catch getting yours at $50.
I have two Puukkos, the R100 Hunting
and the R110 Carpenter
, both are H. Roselli
made in Finland, and both are my Go-To
knives when hunting/fishing/trekking in BC. Both came with their sheaths, but I made another one for the smaller, the Carpenter, in a very nice piece of Cordovan leather, and I'm very happy with it.
Actually the sheath for a Puukko is a very important and essential part of the knife, according to the nordic cutlery tradition.
And I agree with yablanowitz, to have a properly made leather sheath for your Puukko is gonna cost you waaaaay