Cape Air's 402 operation IS 135. Now, many will disagree with me but as a pilot i'd rather fly a 402 than a caravan any day(having flown both). Regardless of what anyone says about PT-6 reliability, there's still one engine there. If something goes wrong, you're probably dead. Honestly the best option I could think of is to talk to Cessna or Piper about building a new replacement aircraft, or maybe even new production 402s. An order for more than 50 should be enough for them to consider it at least. Of course, you might have trouble convincing Cessna to build new ones without fancy avionics and such...
