Need a plugin that disables Buy Now on WP for Age Checks

We have a website that sells products to many, but a few must have the consumer click a box to say they are 18 or over. I have found various 18 related plugins, but they lockout the page or the site.
We just want a simple “I am 18 or over” checkbox, which unlocks the buy Now.

It could be similar to a T&C box I suppose. As long as we can make the text say what we want.

If you’re interested in custom work, drop me an email. I don’t think you’ll be able to find what you need.

PS: Please add URL of the thread, too