As one person living in one of those countries with greatly reduced purchase power, I really appreciate the way Wes Bos[1] has done it for his courses (I've bought a couple of them).

He's got an episode on his podcast on how he implemented it [2].

It does sound like some work and I'm not saying you should discount or give away your work though.

[1]https://wesbos.com/ [2] https://syntax.fm/show/233/hasty-treat-purchasing-power-pari...