The descriptions very slightly between Malory and Brophy's books but it sounds like you have a Model 1894 Short Rifle and/or a M1943 Nazi Occupatin Carbine. These were made durring German occupation and the dimensions are similar to the german M98K. Some were converted from rifles in stock and some were made up from parts. Brophy puts production from 1943-1944 with serial number ranges from 152001-152300 and 301-1000. He also says "The recievers are marked diffrently, but most arms seen have had NA, NB, or NC preceeding the serial number, as well as the German Waffenamt (ordance) stamp."
Unfortunatly, Nord our Norwegian connection hasn't been on in a while, but hopefully he will check in and shed more light on this one.
I would be intrested in seeing pictures. If you can't post them here you could send them to me at nebutts@citlink.net
Ned