Over at HOK Music I found a link to 3 hours of radio at NRK P3, where Lars Finborud (Plastic Strip) is allowed to play his own records, records from the Archives at Henie Onstad Arts Center and recordings from the Norwegian Broadcasting Co. (NRK). He plays a lot of strange stuff, and the most interesting might be the examples from NRKs archives. The contracts clearly stated that only NRK were allowed to play or broadcast these recordings, and they haven't been out on LPs or CDs (so far?).
Listening suggestions: After 24 minutes you get Miles Davis in Oslo 11 September 1971, probably with the crew from the "Cellar Door Sessions". After Davis comes a band fronted by Terje Rypdal from 1972 and around 60 minutes the Sun Ra Archestra come dancing at the Kongsberg Jazz Festival (1982). I'm not sure if these programs stay on the net for a long time, so hurry up if you're interested.