Changing font to a particular repeating character (non-Latin)

Site URL: https://gimel.cc

hey – my store's logo/sign is the Hebrew letter ג, though the SquareSpace fonts do not support Hebrew letters so it looks quite strange. I've uploaded my own Hebrew fonts for that reason but i'd like to create some code that would only change one language or only whenever the character "ג" shows up. 
(I'd like to keep the current English font that i have, only this letter is problematic)