Getting rid of the swaddle

I need some advice.  Eric has been a great sleeper, but has needed a swaddle in order to not wake himself up by startling or scratching (he has eczema on his head).  As he is now approaching five months, we though we would try to break him of being swaddled at night.  It is not going well, to put it mildly.  We finally got the eczema to be a little less severe, so he isn't scratching as much, but he still rubs his eyes and wakes himself up screaming or flails.  We tried doing one arm alone first, and that didn't work.  I've tried giving him his pacifier when he wakes, shushing him with my hand on his chest while rocking his body a bit, but it has been hard to resettle him.  Getting him to go to sleep in the first place is also taking close to an hour without the swaddle.  I really need help.  I would say ok, maybe he isn't ready and we will try it again soon, but he has almost completely outgrown his swaddles (he is almost 20 pounds) and they don't make them any larger.  If I swaddle him in a blanket he gets right out of it and wakes himself all over again.  I'm sleep deprived now and so upset that I can't help him get restful sleep, so any suggestions or advice are welcome!