How to use $product.availability_message to create availability statuses on the product page?

[Konrad Bajsarowicz]

Hi,

I have an online store with antiques. Each product only one piece. I would like to create availability statuses on the product page ($product.availability_message).
1. If the product is reserved (order status: waiting for payment), I would like to display the availability message on the product page: "product reserved" (without the possibility of ordering).
2. If the product has been sold (order status: paid / shipped / delivered), I would like to display the message about availability: "product sold" (without the possibility of ordering).

I am asking for help, how to do it.

[Konrad Bajsarowicz]

This is an example of a product that has been ordered: https://e-antyki.com/brosze/221-broszka-pszczola-zloto-14-karat-agat-szmaragdy.html
The "waiting for delivery" status is displayed here. I would like to modify it as described in the previous post.

Presta version: 1.7.2