I’m trying to use this simple code to insert page (1) content into another page (2):

 <?php
$id = 216;
$p = get_page($id);
echo apply_filters('the_content', $p->post_content);
?>

So far so good. The inserted page (1), though, is some html code that at one point contains

value="<?php echo $url?>"

Is there any way I can edit the value of that variable in the code above, i.e. in page (2)?

Thank you!