How to redownload purchased song on iPhone

I bought a few songs recently, including for example Death Bed by Powfu. Suddenly today several of them greyed out on my iPhone, and I could no longer play them, instead getting the message that the songs are not available in my region.

As a side issue, the whole buying songs through a service instead of on CD philosophy ONLY works when you trust the service NOT to EVER take things away from you that you have bought. If I lose trust in the service, I go back to buying songs in other ways. This is in my mind a deal-breaking breach of trust.

As a test, following some guides online, I deleted the above song, and now I want to redownload it to see if that fixes the problem. However, I cannot see where to find it. I swear there used to be a Purchased play list, but I longer have this. In addition, when I look at Apple's help page for this issue, it talks about a ... button at the bottom of the iTunes app, but this button no longer exists.

Can anyone help?