If you get a motor home 440 it's really not a bad idea to open them up to check it out. I have one and seen where some of my pistons had some edges chipped off so at the very least for me is a pistons will be replaced with new rings and bearings. Yes you will need a new oil pan like Rani said and a 727 from the motor home won't work (I am not sure on that).
Rani while it might be a idea to you to go ahead and drop the 440 in his car isn't really a good idea these Motor home have low mileage but he won't know what kind of abuse it has had. If it pulled a heavy car behind them or carried a lot of weight of top like they were designed to do.
metallicdart if you would like pictures let me know I will take some and send them to you. I may have a extra oil pan for you if you decide to go this route so I will need to check it and make sure if it work.