old instrument, guitar/banjo chinese

As a musician I love to play old instruments from all over the world. Last week I bought a few beautiful old instruments which I think they came from China. Now I am trying to find examples of the same instrument because some of them are badly damaged and I would love to bring it back in the "Original" state. Can anyone read the symbols/letters on the guitar? Or any idea where it might come from and where I can find examples?
Thank you for your time.