thank you for the interesting photos from Finland (kiitos!). As far as I know, the DIEMA in Tervakoski was built in 196x and it is possible (but not sure) that it came from Norway (before 1988).
At "Puhumaan rata" they had (or still have?) a "home made" small moottoriveturi (built 1985) and the Deutz 23509/1939, OMZ 117 F, 6.6 t, which was to heavy for the rails (source: "Resiina" 3/87, page 25).
It would be interesting to see more photos from Finlands narrow gauge here.