There are some 25.4 mm drop bars available. SR used to make them and there are others. They are generally heavy and, therefore, fairly strong since they weren't intended for high line road bikes.

Check out Bike Tools Etc and The Third Hand for sources.

BTW, you have V-brakes so regular road brake levers won't work unless you use "Travel Agent" adapters or Dia Compe's specific V-brake levers.