I haven't done enough research yet on UK. I will circle back to this comment once I do.

I did have a user sign up from Canada, but it's so much simpler there that it probably doesn't make sense for Canadians to pay for Mel:

  1. Fill out the CMA Do Not Mail form: https://cmadnm.cawebhosting.ca/submit.asp

  2. Put a note on your mailbox that you don't want to receive Canada Post Neighbourhood Mail.

For the UK: https://www.mpsonline.org.uk/