For tops, YYF has the best stuff at the best beginner prices in my opinion. You can sell an Elec-Trick(non-LED) and a Short Circuit as a set for anywhere from $15-20. Most people will drop a $20 fast. Remember, you're focusing on beginners, and even new yoyo people won't spend more than $20 on a yoyo normally. The advantage you offer is "I can show you how to use it." That's a major selling point. Tops aren't easy to get started with, especially solo. With help, the odds of success increase tremendously.
I would contact YoYoFactory directly. You'll need a reseller's permit and a minimum order to get started. After that, it's "all your problem", but I'll say if you charge me for shipping, I'll take a couple of each off you. I forget what colors I "need". I like these tops. They aren't the greatest, but they play way better than their retail price suggests. I enjoy playing them.