Yellowhawk,
Those parts are stringers. They aren't a critical structural component as they don't bear loads. They are there to maintain the shape of the skin. On your pictures I would cut the forward stringer at a diagonal and then cut a piece to match it and simply glue them together at the diagonal cuts. Then glue them into the notches in each fuselage former. That will be more than enough strength in the repaired area. Then resheet your balsa over the top of the stringers.

Hope this helps

Ken