That looks like the price for a connection. However, you can get something similar with United or ANA, connecting in Tokyo. I'd highly recommend that versus connecting in Beijing.

Also, are your parents Taiwanese/Chinese (more specifically, do they read Chinese)? My parents make the voyage every few years and mom typically goes to a Chinese travel agency. My parents have frequently purchased their tickets to Taiwan via consolidators that advertise in the Chinese-language newspapers and are located in Chinese neighborhoods (i.e, San Gabriel Valley). These often offer better deals.

All that said, it is high season and that fare doesn't seem out of line. I doubt it'll come down in price.