Yes, you can use residential sleepers in your coach. I did it and so can you.
American Leather Comfort Sleeper is fully modular and they will put it all together for you.
American Leather : Comfort Sleeper
Does your coach have a slide out where your current sofa is located, as the sleeper will need about 80" some odd inches to deploy.
Still, they are shorter than most of the other sleepers by design. They fit flush against the wall.
The Comfort Sleeper is high end and worth what you pay. They have very detailed measurements on their web site so you can be assured a good fit. They also have models with narrow arm rests that allow you a wider bed surface. I have a true queen in my coach....super nice.
Seat belts came right up through a nice open slot at the back of the seat surface and back. You will need to devise a way to secure it to the coach. A little time and thought can get that done. I had to use shorter legs on the back than the front, as the slide floor is raised in the back. I got lucky and just used the shipping legs and put the nice finished wood legs up front. This allows the bed legs to lay fully flat at your feet...very important so you don't bend your bed frame because it's not level with the floor.
You will lose some floor space because the sleeper projects out more than the tiny jack sofa. I did not see this as any problem at all.
I am very glad with my decision...