What door hardware do your need? If you want hinges, TrilliumRV.com has them. If you want a latch, either a Bargman L300, or an L400, they are no longer produced. You can find them on ebay, or kijiji sometimes, but they are not cheep.
I have a pair of hubcaps, they are not perfect, but not bad. They are yours for the cost of shipping.
If you find an opening door window, let me know if there is more, because I am looking for one too.
The replacement hatch is easy if you have a 14" vent. Just buy a Fantastic fan, (or equal). They are fairly easy to install. If you have a 9" vent, like I do, then you are not likely to find one that fits. You will have to cut a hole, big enough for a 14" vent. This is my plan. I also plan to add about an inch high box for the vent and controls to sit in. That way I won't bump my head on the vent fan.