Marrige Records

Hi. I have already posted in the "Norwegians in America" forum asking for help in tracking down certain info on my great-grandfather Oystein (Edward) Wahl. I'm wondering now if there is a way to track down his marriage records. He was born in Nærøy, Nord-Trøndelag in 1895. He left Alaska and headed back to Norway just before World War II and then married Hildur Olsen(Olson) in about 1920. I check the digitised parish registers for Nærøy but the records don't cover the 1920s (http://www.arkivverket.no/URN:kb_read?idx_fylke=17&idx_kilde=Alle&idx_periode=&idx_textsearch=&js=j) He grew up on the "Storval" farm if that helps. Any help would be greatly appreciated. Ryan