Tinn, Telemark - Tinn Soga II - Gaustad and Maarhe

I am looking for data on the mother of Øystein Veaasen - and his parents marriage date and place. It could be in Nord Gaustad, Tinn, Telemark. Øystein Olson Veaasen was bapt 7 July 1798 Klontieg u Rollag, Mael, Tinn, Telemark. On the 1801 census he is age 3. Stranderud  451-452 Øystein's parents are Ola Halvorsson Stranderud Klontieg N Strand born abt 1754 - 1816 and Birgit Øysteinsdatter  born abt 1757   They were married 30 Nov 1784 I am looking for data on Birgit Ø's parents - their marriage - and Birgit's birth date and place. One couple I checked out are at Nord Gaustad - pg 565 Truls Gjermundson and Gunne Nilsdatter - had 8 children One was Anne Trulsdatter who married Øystein Maarheim and had two children - Ole Øysteinson and Bergit Øysteinsdatter. I did not find them at Maarheim. At Nord Maarheim pg 327 - there is a listing of an Øystein Olson born 1723 - no other data. Any suggestions would be appreciated.