Chapter 10/11 spoilers: When do I get Marth and my other rings back? I need to promote a unit to High Priest and need my rings back.
You get the other 6 rings that you didn't have before across chapters 11-15, then you get the 6 rings from the first part of the game back a couple at a time in chapters 16-20. Unfortunately, the rings that give magic proficiency are among the last ones you get back, so you're locked out of that class until like chapter 19. Can't remember the exact chapter numbers, but those are about the right ranges.