RE: obeche veneer
There should be specialty lumber stores in your area that carry veneers. Unless I was building something really huge, I wouldn't use this stuff for wing sheeting because it is heavier than necessary. .60 sized pattern planes do very well with carbon strip "spars" below 3/32" balsa sheeting. I don't think anything could be simpler, lighter, stronger and still relatively cheap [for a foam wing technique].