There's a Czech bass for sale here in Chicago, made ca. 1927 by Vaclav Nosek. Does this name mean anthing to anyone. What I have found are some references to violins made by Nosek in the late 1920s that seem to be well regarded and sell for decent amounts ($4k - $7k). He worked near Trest, a resort area in Moravia.
In my little experiences, Czech string instruments have always been of a very high standard. An 80 year old Czech Bass would probably be worth a LOT. But you probably knew all that.