Can a friendly letter have a closure using the word "from"
There are many closures for letters, the classic one is "Yours truly,"
Personally I don't like this type of ending, unless I am writing to a family member or lover. Even then in those cases I would probably end the letter with simply "Love,"
If the acquaintance is not one of the above, I would normally use "Regards," or more friendly and polite "Kind regards," or "Warm regards,"