Not seeing song to buy

The CD that contains that song is available on Amazon, used, for less than $2. If you owned the CD, you would have the right (in the U.S.) at least, to rip the track to your computer.

I would also note that neither the album nor the track seems to be available for digital download on Amazon, either.

Mistaken by Warren Barfield is also not available here (EU) from the iTunes Store.

Mistaken by Warren Barfield can be listened to via Apple Music subscription.

If II buy it from an Apple Music subscription, will it be accessible to my iTunes account? Then could I cancel the Apple Music subscription?

If you cancel the Apple Music subscription you cannot listen any more.

It is iTunes Store policy not to sell the Mistaken by Warren Barfield song.

We cannot help you, we are also users of Apple products & services like you.

Get support from Apple directly -> Get Support or call Apple in your region see -> Contact Apple for support and service