Thanks!
Ad 1)
Look at [language designator]_[region designator] here https://developer.apple.com/library/content/documentation/MacOSX/Conceptual/BPInternational/LanguageandLocaleIDs/LanguageandLocaleIDs.html#//apple_ref/doc/uid/10000171i-CH15
Ad 2)
Yeah, OSX is definitely something I should take a look at. What new price do you suggest? 🙂