Aero Stye RGC lever like those are highly undervalued IMO, but being that it is Diacompe, and not Suntour or Shimano, would always give them that almost second tier image to most cyclist, despite their high quality...
Being that they look to be NOS and minty fresh looking, I would not hesitate to ask at least 60 bucks for the set....heck people had been asking and getting more than half that money for good NOS lever hoods!