"Cottage Industry" Jets
I think producing an old style turbine costs just as much as making the new one.
That would be like saying why doesn't someone make a "new" 1965 mustang and sell it for 3500 dollars.
There are some very cheap used turbines out there. Usually the manufacturers went out of business.
The words "cheap" and "turbine" don't really seem to go together. Even if one got down to $1000, the person who paid that will expect the same level of service that everyone is getting these days. They want someone on the phone, the internet etc to fix problems. and they will still have to be hooked up and troubleshot the same as the others.