More pictures here: http://ackegura.proboards.com/thread/13911/harpgitarr-objekt-till-en-gammelgura
A very similar harp guitar that I recently fixed can be purchased by a collector in Germany for 120 EUR + shipping (usually about 20 EUR). The thread on the former can be found here: ackegura.proboards.com/thread/13884/gammelgura-31-harpgitar-ca-1920. Most likely it is the same Swedish manufacturer with the difference that this one has 6 bass strings. This one was sold in Norrköping between 1899-1911. Inquire about your PM or mail (which you will find on the site www.gammelgura.se) if you want to bet on this one as an Old Gura!