It's off topic, but:
Availability of Rhenium will not be an issue when ceramic matrix composite (CMC) turbine blades become the norm.
I was involved with research into ceramic materials for static engine components in the early 90s. Specifically Silicon Nitride in the form of SiAlON as well as Silicon Carbide.
Neither of which were viable with the technology of the time, even for static parts, but lots of original work lead to a greater understanding of material properties and advancements in manufacturing.
CMCs are beginning to worm their way into commercial and military engines (see LEAP, GE9X and of course F135 exhaust nozzle). Those applications are all static components, but it's only a matter of time. I'd say about 20 years considering the development cycle.