I would be surprised to find a professional company that would accept a job of this scope for less than 2K. However, that same company would have overhead (hosting costs, online fees, phone, maybe fax, hardware and software to keep recent, etc.) and you have to factor in time spent getting the job and talking to the client. Not all, or even nearly all, of the 2K+ is going to be raw profit. And how much time are you going to spend on the job? Probably quite a bit. And what if the client doesn't pay up? You still get paid.

Bottom line, there's no way to tell how much profit your boss is making off the programming. However, from an hourly wage point of view, $15 / hour sounds does sound a bit low if you do fast, professional work. If you're the only programmer working for him and have finished at least college, I'd push for a bit of a raise, or better yet, a cut of the action.

EDIT: But if you're interning, $15 / hour is fair.