WP_Query: button in event list

I’ve written -thanks to this forum- this function which calls a number of events from a wp_query.
Now i want to insert a ‘Make a reservation’ button only for the events where reservation is allowed.
Can somebody give me some advice how to insert a ‘booking possible’-check ?
Thanks !

function the_recent_agenda ($post_num=5){ 

		$args = array(
		'post_type' => 'event',
		'posts_per_page' => 100,
		'meta_query' => array( 'key' => '_start_ts', 'value' => current_time('timestamp'), 'compare' => '>=', 'type'=>'numeric' ),
		'orderby' => 'meta_value_num',
		'order' => 'ASC',
		'meta_key' => '_start_ts',
		'meta_value' => current_time('timestamp'),
		'meta_value_num' => current_time('timestamp'),
		'meta_compare' => '>='
	);

		$query = new WP_Query( $args );

		// The Loop
	while($query->have_posts()):
	$query->next_post();
	$id = $query->post->ID;
		?>
  <div class="span3">
    <div class="BlogArticle">
      <div class="ImgWrap"><span class="date">
      <?php $eventd = get_post_meta($id, '_event_start_date', true);
	  $eventok = strtotime($eventd);
	  ?>
        <?php echo date("M", $eventok); ?>
        <br />
        <span>
        <?php echo date("d", $eventok); ?>
        </span></span>
        <?php if(has_post_thumbnail($id)){ 

                             ?>
        <a href="<?php echo get_permalink($id); ?>">
        <?php echo get_the_post_thumbnail($id); ?>
        </a>
        <?php

                        } else{
                            ?>
        <a href="<?php echo get_permalink($id); ?>"><img src="<?php echo get_template_directory_uri();?>/images/03.jpg" alt=""></a>
        <?php
                        }?>
      </div>
      <div class="WhiteTone"> <a href="<?php echo get_permalink($id); ?>"><span class="title">
        <?php echo get_the_title($id);  ?>
        </span></a>

      </div>
    </div>
  </div>
  <?php
endwhile;
}

http://wordpress.org/plugins/events-manager/