The best investments he could possibly make are a scale model/replica Gutenberg movable-type printing press and books on important early modern (like Enlightenment era) topics like metallurgy, medicine, and chemistry. If Shangri-la has an ebay-style used goods section he could buy a used and working scale model of the Gutenberg press for like 200-400 dollars. You can actually buy a working scaled replica Gutenberg press from a Biblical museum store for $700, but that would be way out of the scope of any ordinary e-commerce site and would be unlikely to be found on Shangri-la. Failing that, he should buy teaching materials like posters, diagrams, and books about the early history of printing presses.
It would be on him to translate the materials, but once he has a translated manuscript for these books he and his business partners would have commercial ownership of the most important founts of knowledge in the known world, and would probably hold that knowledge for at least a decade before someone would figure out how to replicate the press and start mass producing unauthorized copies of the translated texts.
Actually... fuck, if you can buy a prefab log cabin on Shangri-la you can certainly buy a Gutenberg press. Are you shitting me? A whole log cabin? Might as well buy penicillium cultures and replica 1700s microscopes. Fuck, buy a whole Bessemer converter. A log cabin? Jesus.