Zaxo's answer above is spot on. On a slightly different take, you may wish to use a hash to make your code a little clearer:

# pick a better name -- I don't know what the data represents
my %srhash = (
    SRADDL => "SRC Addlf",
    SRSUPP => "SRC Supp",
    # and so on
);
$ora = $srhash{$dtype} || $dtype;
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