Ah, that was the answer I was looking for. Actually ppm didn't find the package among the repositories I use :(. However is did stimulate me in to looking for other similar modules. For that, thank you! :)

In the end I used Data::SearchReplace:

use warnings;
use strict;
use HTML::TreeBuilder;
use Clone qw(clone);
use Data::SearchReplace ('sr');
 
my $newHTML = 
  ['div', {class => 'ourobject'},
    ['script', {language => 'JavaScript', type => 'text/JavaScript'},
      'embedLabTutorClient("VIEW", "URL", WWW, HHH)',
    ],
    ['noscript',
      ['object',
        {classid=>"CLSID:ReleaseCLSID", width=>'WWW', height=>'HHH', v
+iewastext=>'1'},
        ['param', {name=>'ViewSettingsUrl', value=>'URL'}],
        ['param', {name=>'ViewName', value=>'VIEW'}],
      ]
    ]
  ];


my $objUrl = 'somewhere/object.obj';
my $objView = 'erewhon';
my $objWidth = 255;
my $objHeight = 127;

my $copy = clone ($newHTML);

sr {SEARCH => 'WWW', REPLACE => $objWidth}, $copy;
sr {SEARCH => 'HHH', REPLACE => $objHeight}, $copy;
sr {SEARCH => 'VIEW', REPLACE => $objView}, $copy;
sr {SEARCH => 'URL', REPLACE => $objUrl}, $copy;
    
my $element = HTML::Element->new ('root');

$element->push_content ($copy);
print $element->as_HTML(undef, '   ', {});
[download]

Prints:

<root><div class="ourobject">
      <script language="JavaScript" type="text/JavaScript">embedLabTut
+orClient("erewhon", "somewhere/object.obj", 255, 127)</script>
      <noscript>
         <object classid="CLSID:ReleaseCLSID" height=127 viewastext=1 
+width=255>
            <param name="ViewSettingsUrl" value="somewhere/object.obj"
+>
            <param name="ViewName" value="erewhon">
         </object>
      </noscript>
   </div></root>
[download]