I thought there were some threads on this topic before, but I'll offer my experiences. Peds-->peds EM in general doesn't pay as well as adult EM. For example our most recent fellow just finished his fellowship and is looking in the lower northeast for jobs (New Jersey, Philly). His offers have been around 170k range (12 or 13 shifts a month plus expected lecture and some research time). This salary would go up over time as he progresses academically.
There are some private groups out there that pay more, but this is a little harder to find. One of our recent fellows took a job out in Washington state with a private group. He's making near 250k or so. I also saw another, similar offer/advert from a small ED in Vermont that wanted someone peds trained to take those cases. I haven't seen many of these however and these were 'adult' groups that didn't want to deal with kids coming in.
Some of the other adult guys here may actually know of more setups like that, but I don't know many.