You can call Heartland Customer Service at 877-262-8032 / 574-262-8030. Have your VIN # ready. Ask for parts.
The should be able to get you the same size doors as what you have, with the same finish (if a recent build). You'll need measurements and clear pictures. It'll also be helpful if you now the decor name for your trailer's interior.
This is a custom order, so it may take a few weeks extra to get them.