There are two issues with mobile home cabinets:
Can I repair/refinish the ones I have?
Can I replace them with stock cabinets from the home improvement centers?
Finding replacements for one or two individual cabinet doors is a problem for which I do not have good answers.
If the home is VERY new it may be possible to get replacements from the factory. Talk to your dealer and ask them to contact the factory parts person to see if they are still using the same materials.
Sometimes the setup companies and mobile home repair businesses that do a lot of new home trimout will save discontinued materials they happen to have in stock. There again, the dealer is the source most likely to know who might have them.
I know people have tried a variety of stains, cleaners, sprays and contact papers in an effort to make their existing cabinets look better. Unfortunately, there is so much variation in original materials and application skill that I can’t really offer any useful advice. I suggest you try a treatment in an out of the way spot first and see how it goes.
If you can possibly afford it, installing new cabinets will make a dramatic improvement in your home. With the development of computer controlled milling machines the home improvement stores have begun to carry an astonishing variety of pre-cut, assemble yourself, cabinets. They come in several types of wood, many finishes and a whole range of costs. This is probably you best bet for a close match with your existing cabinets. You may even find it works to buy them unfinished and then finish them to match your existing woodwork.
Remember that cabinets, especially good ones that are filled with stuff are HEAVY. You can’t hold them to the wall with butterfly nuts through the wall panels! Make sure you get lots of screws deep into the wall studs.