installing other country's firmware

can I install other country's(SM-G850M) firmware to my Galaxy alpha (SM-G850M)? it says in its box it was made in Vietnam but it was brought from UAE(my friend brought it) that's why I don't know which country's firmware to install!!! and firmwares for SM-G850M are only for South American countries. PLEASE, PEOPLE, HELP ME. THANK YOU SO MUCH.

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