Change Price Display to "Sold Out" on Sold Out Items

Hello,

I am trying to remove the price from being visible of sold out items on this specific shop page. (https://www.natederidder.com/originals)

If possible, I would like it to say "SOLD OUT" instead of showing the price of sold out items. 

Add to Page Header

<style>
  .sold-out .product-price {
    display: none !important;
}
</style>