Jeremy,
I don't think its technology that will make these things cheaper, it supply and demand. If these turbine company's could afford to have a run of a thousand of each piece made at one time and be able to sell the engine fast when they are done then you will see the price come down. The cost to do this will be in the millions, just to hard to do!

These engines have to be made to certain standards, if you do see the price to low things are being compromised to make it so cheap.
Thats why I say support the turbine mfg's that already exist. Hopefully they will exist and continue to make these engines for you. Their experience on these engines surpass any new guys coming out.