Finding and producing raw materials is not a problem. Despite the name "rare earth" they are not actually as rare as the title implies, consumption has historically just been too low to require even middle priced mining of them. Just as redpoint5 says, its supply and demand pricing. With enough financial incentive the materials will be found and processed. I spent 11 years as a copper geologist, now I'm a lithium geologist working on bringing a mine online that on its own would be a 1/4 or todays production, but likely will be around an 1/8th of the worlds production of lithium when it gets going full tilt (up and running in 2-3 years, another year or 3 to hit full tilt). Any comodity just needs enough demand pricing.
Also, there are alternative to rare earth magnets for electric motors, just a little less efficient.