That is one nice-looking folder! I agree that it's probably an early-production Belfoca. The history is confusing---VEB was a conglomerate that absorbed Belca sometime in the mid-1950s in Dresden, but by that time they would have been using the name "Belca-Werk" rather than "Balda-Werk". (The Prontor-S was introduced in 1951 and I think it was the usual higher-grade shutter on these cameras.) It might have been a transitional body of some sort, and maybe that back door with the single red window was cannibalized from something else entirely---I can't find any Belfocae or Fixfoci with that spiffy sliding cover.

One caution---sometimes the reason an old camera looks brand-spanking-new is that it didn't work well! I've got an absolutely lovely 1920s Voigtlaender that clearly was unusable from the factory---the lens is misaligned in a way that makes it impossible to get anything in focus and that would require precision metalworking to fix. Hopefully you don't have that situation, but it would be good to run a roll through (I know we have members in Boise; step up, y'all) and check basic functionality.

-NT