Pixelpiper
Super Freak
Oh man, I wish I could use that because it would save a ton of money, but I just tried it out in my postage software and I would definitely lose the delivery confirmation.
Just a tip, but even though "Delivery Confirmation" may disappear from the settings, it continues to work for a number of countries like the Netherlands, Spain, Belgium, Brazil among others.
For some countries, you can't get any tracking at all with First Class and you have to use Priority, such as South Korea. Now THAT gets pricy.