If you need a high-quality Japanese sans-serif (Gothic) font with a similar weight and feel but without the cost, consider these free, open-source options: Noto Sans JP (Black or Bold): Available for free via Google Fonts . It is designed for maximum readability across languages.
The PDF may have embedded the font incorrectly. In Adobe Acrobat, go to Edit > Preferences > Page Display and uncheck "Use local fonts". This forces Acrobat to use the embedded subset. Hiragino Sans W7 Font Free Download