Bulova 1949 Commodore

As there is no shock protection on these movts, similar to many of the period, balance staff breakage was common. Sideways shock is the most damaging, as the pivots will just shear off. Dropping the watch often had the same effect.

Although IncaBloc was invented in 1934, shock protection did not see widespread use until the 50's. 

I suggest trawling eBay for either a donor movt or donor watch, and as other models had the same movt, you can expand your search to include them from the same period.