Brent, it would seem a quite similar idea, Pasi uses coarse thread wood screws to make it fail-safe. I have no idea historically when secondary attachment started, but would guess quite far back in time on a 1000yr old hard hard use knife design, and them coming apart as a nomadic arctic herder a very bad thing. But whether wedges, nails, crosspins, or whatnot, absolutely no idea at all.

As for one of these days, the exchange rate not bad at all, Finland is loaded with educated unemployed folk attending formal schools of native art preservation, much competition for business, and if one can afford any handmade knife at all, one can afford one of these.

HOWEVER, they ain't for everybody, and handling them goes against a lifetime of knife handling habits by folk in the USA, such as if you elevate the tip and not locked into the one secure rear grip on these knives, you WILL need a bandaid or stitches, and maybe orthopaedic surgeon if you stab out of habit. A good friend who knows his way around knives enough to have been an "agricultural inspector" in Vietnam has a pinky which has never worked again after a careless moment with some unknown puukko, and you could not pay the man to touch another one.

Windsor, the fit is via wet molding which is why the plastic wrap of blade and handle. Often, the sheath body was split and carved out antler pinned back together, and the leather neck of sheath shrunk around grooved antler up top and sealing the mouth. The intricate carvings of the Suomi, Sami/Lapp herders marvels of art.

This is a modern artist take on such work, with a step by step available at the nordisknivär site of
https://nordiskaknivar.wordpress.com/2016/03/28/roman-kislitsyn-sami-style-carving-wip/