You can add this code snippet to display special order status. This may require the assistance of a developer.
<ul class=”product-tags”>
{% for tag in product.tags %}
{% if tag contains ‘SpecialOrder:Y’ %}
<li>This is a special order item, please allow an additional 15-20 days delivery.</li>
{% endif %}
{% endfor %}
</ul>
Shopify handles the display of in/out of stock (or availability) in most themes.
You can see how to do this in our Shopify – Manufacturer Part Number Quick Tip.