I'd use an array of hashes.

use List::Util qw( first );
my @user_types
    = ( { name => 'member',
          numb => '037', },
        { name => 'public',
          numb => '165', },
      );
my $selected = first { $_->{name} eq $cgi->param( 'foo' ) } @user_type
+s;
$selected ||= $user_types[0]; # in case nothing is selected
my $selected_numb = $selected->{numb};
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If you don't want to use List::Util::first, you can use grep instead (the list is short). It's easy this way to add any info you want to each element (e.g., a 'key' you put in the HTML form plus a human friendly name that you show to the user). Inside your script you can tie as much data as you want to each element.