Ok, first, what is a 48 3/4 and 46 1/4? Couldn't understand that.
I believe this bass is German. Basses for the most part here in USA called Czech basses are mostly basses made on either side of the German-Czech border and mostly made by German speaking makers. On occasion there are some Czechs working on there as well.
These are made in shops usually and sometimes with outworkers making parts and assembled in the shop. These are not usually made by a specific single maker.
The Tuners tell me that it is probably a post war bass as I have the exact same tuners on my 1970 Pollmann, similar ones on my 1980 Pollmann and had there on my Wenzel Wilfer bass, probably post war. I have also seen these on East German basses made by Saumer for the Morelli brand. Other brand names created by importers have been used for these same basses as well.
The main centers for basses like this were made in Markneukirchen and some in Bubenreuth in Bavaria. Pre-War, they were also made on the Czech side by the same families in and around Shoenbach, also known as the Sudetenland, the German speaking area across the Czech border.
Read this;
http://www.smithbassforums.com/showthread.php?t=2176
Now, I am not from these areas or lived there for centuries to know all this but, I have read and studied what I could find in person and in reading. Most can do the same.
Here are two actual Czech basses made in the Viennese style from the 19th century, c.1850. Flush ribs and beautiful scrolls as well as transparent varnishes without shading or artificial aging. Totally different than the German border basses imported into the USA since the turn of the 19th-20th centuries.
http://www.kensmithbasses.com/double...gue/index.html
http://www.kensmithbasses.com/double...ina/index.html
Basses in the 18th century might differ some from those in the 19th and also 20th centuries. As time goes on, so do the style of double basses.