Three words.
Republic of Tea.
Do eet. If it isn't Harney & Sons, it's Republic of Tea here. One tea bag is equally good for a single cup or an entire tea ball. I could probably brew one twice if I was really desperate like when back in college. And, you can buy bulk bags to save money. I end up getting a bulk bag of something once a year and tossing them into an old apothecary jar so it looks all fancy like I meant to do that and I'm not being cheap at all. They have loose leaf too but if I poured that into the jar, I'd never get it out.