Biscuit74
The engine problem is one of limmited availability , production of parts stopped some years back And unlike the Gypsy there is no big stockpile of parts from years of production or large support network.
Due to leagal issues with the airframe the inspection would return this to almost new standard so no operator is going to invest a sum of capital In an airframe that has an engine with a very uncertain future.
Find someone who wants a fleet of 20+ aircraft and has the cash and the project would work, the result of spreading the cost across twenty or so units would also bring down the unit cost a little.