Peter
I'm sure adding a multi to your licenses would be a very simple and cheap thing.
If you did, you could be travelling in what you say is the kind of plane you require for your missions. For $300K you could be in a MU-2 tomorrow that burns only marginally more than a turbine single. Fuel consumption follows SFC and horsepower, therefore a twin never burns much more than a single with equivalent horsepower. Also, the Garretts are more fuel efficient than the PT6s. The MU-2 does 300kts, FL300 with all the mod cons. That would be twice as safe as a TBM850 and would leave you $1million to spend on fuel.
Or a Conquest or Turbine Commander. But the MU-2 is the most bang for the buck. Well supported as well. And if you've ever been close to one, you know how well built they are. No oil canning panels there...