Can anyone tell me the age of my Juzek bass?

[Nelson Cascais]

Hi

I would like to know more about my Juzek bass.
It´s a small bass, maybe 5/8, i´m not sure...

Measurements are:
upper bout; 18.5"
center bout; 13.5"
lower bout; 24.5"
depth of Ribs: 7.5 "
length of body: 41"
String Length: 40.1"

It´s very healthy. There´s only some well repaired cracks in the ribs.
The tuning gears were replaced but I still have the original ones.
The label says:
"John Juzek, Violin Maker, Formerly in Prague, Made in Germany"
The person who sold it to me told me that it is a pre-war Juzek, from the 30´s.
Is it correct? What could be the estimated value for this instrument?

Thanks a lot
Nelson