I cant find a tag but after seeing lots of older Gibson instruments this has the same wood types and design. There is a repaired crack on the back and about 8 of binding is missing from the bottom on the backside.
After a little repair and cleaning/ strings this will tune up nicely and hold. The item "Gibson Concert Zither" is in sale since Wednesday, July 22, 2020.
This item is in the category "Musical Instruments & Gear\Vintage Musical Instruments\Vintage String\Folk & World\Autoharps & Zithers". The seller is "indiemusic603" and is located in Milford, New Hampshire.This item can be shipped to United States.