Replace the 'None' option text in Subscribe All The Things with the product's price string.

satt_replace_none_with_price.php

<?php

add_filter('wcsatt_single_product_one_time_option_description', 'satt_replace_none_with_price', 5, 2);

function satt_replace_none_with_price ($none_string, $product) {
    
    $none_string = _x( '' . $product->get_price_html() . '', 'product subscription selection - negative response', 'woocommerce-subscribe-all-the-things' );
    
    return $none_string;
    
}