adds MSRP price to woocommerce admin and display

functions.php

add_action( 'woocommerce_variation_options_pricing', 'bdev_add_variation_msrp', 11, 3 );
function bdev_add_variation_msrp( $loop, $variation_data, $variation ){
    woocommerce_wp_text_input( array(
        'id' => '_msrp_'.$loop,
        'wrapper_class' => 'form-row form-row-first',
        'class' => 'short wc_input_price',
        'label' => __( 'RRP / MSRP', 'woocommerce' ) . ' (' . get_woocommerce_currency_symbol() . ')',
        'value' => str_replace('.', ',', get_post_meta($variation->ID, '_msrp', true)),
        'data_type' => 'price',
    ) );
}

add_action( 'woocommerce_save_product_variation','bdev_add_variation_msrp_save',11 ,2 );
function bdev_add_variation_msrp_save( $variation_id, $loop ){
    if( isset($_POST['_msrp_'.$loop]) )
        update_post_meta( $variation_id, '_msrp', wc_clean( wp_unslash( str_replace( ',', '.', $_POST['_msrp_'.$loop] ) ) ) );
}

add_filter( 'woocommerce_available_variation', 'bdev_add_variation_msrp_display', 11, 3 );
function bdev_add_variation_msrp_display( $data, $product, $variation ) {
    if( $msrp = $variation->get_meta('_msrp') ) {
        $data['price_html'] = '<div class="woocommerce_msrp">' . __( 'RRP / MSRP: ', 'woocommerce' ) .
        '<span class="msrp-price">' . wc_price( $msrp ) . '</span></div>' . $data['price_html'];
    }

    return $data;
}

add_action( 'woocommerce_product_options_pricing', 'bdev_add_msrp_to_product' );
function bdev_add_msrp_to_product() {
    global $product_object;
    woocommerce_wp_text_input( array(
        'id' => '_msrp',
        'class' => 'short wc_input_price',
        'label' => __( 'RRP / MSRP', 'woocommerce' ) . ' (' . get_woocommerce_currency_symbol() . ')',
        'data_type' => 'price',
        'value'       => str_replace('.', ',', $product_object->get_meta('_msrp') ),
    ) );
}

add_action( 'woocommerce_admin_process_product_object', 'bdev_add_msrp_to_product_save', 10, 1 );
function bdev_add_msrp_to_product_save( $product ) {
    if ( isset( $_POST['_msrp'] ) )
        $product->update_meta_data( '_msrp', wc_clean( wp_unslash( str_replace( ',', '.', $_POST['_msrp'] ) ) ) );
}

add_action( 'woocommerce_single_product_summary', 'bdev_add_msrp_to_product_display', 9 );
function bdev_add_msrp_to_product_display() {
    global $product;
    if ( $msrp = $product->get_meta('_msrp') ) {
        echo '<span class="woocommerce_msrp">' . __( 'RRP / MSRP: ', 'woocommerce' );
        echo '' . wc_price( $msrp ) . '';
    }
}