Linefeed is 10 in decimal => 12 in octal, and you can combine three of your substitutes into a single character class:

    $text =~ s/[\000-\011\013-\037\177-\377]/ /g;
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Or, using a POSIX character class, the much more readable

    s/[^[:print:]\n]/ /g;
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See perlre for a full list of the POSIX character classes