Usually when someone posts something unusual on here I can say to myself (since no one I know would give a hoot) "I remember that!" Even if I never cleaned it up for resale there was probably at least one out in the back parking lot waiting for the scrap guy to come by. I don't ever remember seeing a range with a built-in roaster...very cool. The closest thing I recall were a few with pressure cookers in place of the well cooker.
As far as I know, I have all three of the pressure cookers ever made for deepwells. GE had the one made by Ekco, Prestline ranges used one made by Presto and Westinghouse and Frigidaire had Mirro-Matic pressure cookers. They were horribly bulky and heavy compared to the usual deepwell pan and probably very heavy to lift up from the usual left rear position for many women and it had to be lifted out at the end of cooking or the pressure would take forever to go down, but when pressure cooking was all the rage, for the first time, in the late 40s and early 50s range manufacturers found a way to tap into the craze. All but the GE were very hard to find.
Kenmores was actually a cast aluminum electric skillet type thing, I have seen one only once, the Monarch was actually a regulation roaster with a porcelian insert and side heat, Monarch also had what was called a Deep Heat saucepan, the heat for this deepwell was also in the sides of the well and not the bottom, they made some wierd stuff, thats why I like it!!!