I do not know about the couch to booth conversion, there is a water tank under the couch.
As for the door, if it will close then you should be able to persuade it to close properly. The exterior skin has to be removed and the door carfully bent back into proper shape with muscle power and possible stratigic placement of a 2X4. Once the door is correct then you re-rivet the interior skin back on with new holes and rivets.
Some vintages had cast door frames, if this is the case then bending will not work. If the frame on yours is extruded then you will be able to fix it yourself. Replacements will be hard to come by.