<span id="ProductPrice" class="product-single__price" itemprop="price">
{{ product.price | money }}
</span>
Something like this might work
{% if variant.available %}
<div class="product-single__prices">
<span id="ProductPrice" class="product-single__price" itemprop="price">
{{ product.price | money }}
</span>
{% else %}
UNAVAILABLE
{% endif %}
