Get all posts from custom post type and insert in select input as metabox

I would like to know if its possible to do something like this. I have Slider custom post type and Services custom post type.

For slider posts I have created a metabox for URL value to display next to all slider posts. What I would like to do now, is to get all posts from Services custom post type, and display them in this slider post metabox as select input, so I can choose which post should the link go to.

Thanks in advance 🙂

Here is the current code:

function rm_display_slider_metabox($post) {

    wp_nonce_field(basename(__FILE__), 'slider_nonce');

    $slide_url_value = get_post_meta($post->ID, '_slide_url', true);
    $slide_url = isset($slide_url_value) ? esc_attr($slide_url_value) : '';

    $services_loop = new WP_Query(
        array(
            'post_type' => 'services',
            'posts_per_page' => -1,
            'post_status' => 'publish'
    ));


?>
    <div class="slider meta">
        <p>
            <label for="slide-url"><?php _e('Select URL from the dropdown below for this slide', 'rmtheme' ); ?></label>
            <br />
            <select name="_slide_url">
                <?php while ($services_loop->have_posts()) : $services_loop->the_post(); ?>
                    <option value="<?php the_permalink(); ?>"><?php the_title(); ?></option>
                <?php endwhile; ?>
            </select>
        </p>
    </div>

<?php 

}

function rm_save_slider_meta($post) {

    global $post;

    if (defined('DOING_AUTOSAVE') && DOING_AUTOSAVE)
        return $post_id;

    if (!isset($_POST['slider_nonce']) || !wp_verify_nonce($_POST['slider_nonce'], basename(__FILE__)))
        return $post_id;

    if (!current_user_can('edit_post'))
        return $post_id;

    $allowed = array(   
        'a' => array(
            'href' => array()
        )  
    );

    if (isset($_POST['_slide_url']))
        update_post_meta($post->ID, '_slide_url', wp_kses($_POST['_slide_url'], $allowed));

}

add_action('save_post', 'rm_save_slider_meta');
add_action('add_meta_boxes', 'rm_slider_metabox');