Hi Amy -
My DS was a "rocker" for a while, too, even though I technically didn't even have a rocking chair until he was 7 months old...up until we had a rocker, I used two techniques that seemed to simulate rocking fairly well:
#1 was I sat on the bed crosslegged, with a pillow on my lap, and cradled him in my arms and sort of sway/rocked - it wasn't comfortable for a very long time, but I would just keep telling myself, "just another couple minutes, just another couple minutes" - and eventually that was true! HA!
#2 was that I propped pillows up at the head of the bed, leaned back into them with my legs bent up, and just kind of slowly rocked back and forth that way, sinking into the pillow and coming back up out of it. That was more comfortable for me.
Eventually, I got DS to tolerate being "swayed" left to right just as much as being "rocked" back and forth, so that helped out in the no rocking chair situation (r if I was too lazy to go upstairs to the chair and wanted to stay on the couch!).
Oh yeah, I also developed a pseudo rocking motion that I could use while reclining in bed with him on my chest (My son is 16 months now, and I can still do this with him in a pinch) where he lays diagonally across me, with his head in the crook of my arm, and I just kind of sway back and forth and move my arm along with the swaying motion (I know that may be hard to visualize, but if you get him into that position it might just come naturally)...that way you're not "laying down", so he'll feel more familiar with it, but you're reclining, so it's more comfortable on you...that's how I eventually transitioned him to being able to lay down in bed next to me and drift off together while we snuggle...I just kept reclining on the bed more and more, week by week, until I ended up horizontal. Then again, he had stopped nursing to sleep by that point (he would nurse and then unlatch, and then fall asleep) so I didn't have to do them both at the same time.
I agree with the PPs and would just start experimenting in your own bed with different positions that will be comfortable for both of you, so that by July you're in a groove.