SimplePie WP-filter specific posts from multiple blogs

<?php  ///Start of SimplePie
    //Add your feeds here
    $rsslist = array( 'http://www.worldoweb.co.uk/feed',
              'http://www.alfiemilne.org.uk/news/feed');

    $rss = fetch_feed($rsslist);

    if (!is_wp_error($rss)) :

        $maxitems = $rss -> get_item_quantity(10);//change item quantity if needed
        $rss_items = $rss -> get_items(0, $maxitems);
    endif;
?>
/*The below function strips the first image from the feed. May or may not be useful*/
<?php
    function get_first_image_url($html) {
        if (preg_match('/<img.+?src="(.+?)"/', $html, $matches)) {
            return $matches[1];
        }
}?>

<ul class="rss-items" id="wow-feed">
<?php
if ($maxitems == 0){
    echo '<li>No items.</li>';
}
else {
    foreach ($rss_items as $item):
        $id = $item->get_id(); //Get's IDs of posts

        //echo var_dump($id);//  Uncomment, save and reload browser to display ID's

        //Replace below with your ID's, can be from different blogs etc
        $id_list = array('http://www.worldoweb.co.uk/?p=5787','http://www.worldoweb.co.uk/?p=5941','http://www.worldoweb.co.uk/?p=5807','http://www.alfiemilne.org.uk/news/?p=1225');

        if (array_keys($id_list,$id)) {?>

        <li class="item">
            <span class="rss-image">
              <?php echo '<img src="' . get_first_image_url($item->get_content()) . '"/>';?>
            </span>
            <span class="data">
              <h5>
                <a href='<?php echo esc_url($item->get_permalink());?>'
                title='<?php echo esc_html($item->get_title());?>'>
                    <?php echo esc_html($item->get_title());?></a>
              </h5>
            <span class="date-image">&nbsp;</span>
                <small><?php echo $item->get_date('F Y');?></small>
                <span class="comment-image">&nbsp;</span>
                <small><?php $comments = $item->
                        get_item_tags('http://purl.org/rss/1.0/modules/slash/', 'comments');?>
                    <?php $number = $comments[0]['data'];?>
                    <?php if ($number == '1') {
                            echo $number . "&nbsp;" . "Comment";}
                            else {
                            echo $number . "&nbsp;" . "Comments";}?>
                </small>
                <p><?php echo $item->get_description();?></p>
            </span>
        </li>
        <?php } //end if?>
        <?php endforeach;?>
        <?php } //end if;?>
</ul>