This is Finnish made telephone, Puhelinliike Arsa in Salo. Founded 1943 and was first making telephones and switchboards. Soon changed to make electrical centers and their cases, which their still are producing.
Cabinet of phone made by local cabinetmakers from birch, stained and French polished.
Parts taken from field phones bought from Finnish army after second word war. Handsets bought from Finnish Puhelinteollisuus.
This one seems to be made 2.6.1948.