7% chargeback rate is insanely high and I wouldn't be surprised if your merchant dropped you. Realistically anything over 0.5% and you're doing something wrong and that's even a magnitude higher than what I would shoot for.

Also, selling at $1 you're only going to make $0.67 or so per transaction (maybe less depending on how you get bilked in fees). You're going to have to do a lot of volume to make money selling at $1.