If you like what you've got, maybe get another Peterson? Cup-O-Joes prices can be beat but they have quite a few Petersons, or did last time I was there. And they are a good firm to do business with.
You might also try smokingpipes.com and pipesandcigars.com.
If you're wanting a different brand, there are many, many carvers/companies that can supply you with a satisfactory pipe: Stanwell (their quality has been very good, but they moved the factory recently, and I don't know about the quality of the pipes that they're currently producing), johs, neerup.
If you buy estate pipes (used) you can literally double your money, get twice the pipe that you could get buying it new. That's how I buy most of my pipes. smokingpipes and The Pipe Rack are good places to hunt for low-cost estates.