Mobile Home cabinets are some of the cheapest, poorly constructed furnishings known to man. They are frequently made of paper and held together with staples. In addition, the manufacturers build them them themselves from a variety of supplies. The supplies change frequently to meet changes in decor and lower prices from vendors. In other words, mobile home cabinets frequently have problems and it is impossible to find matching replacement materials. You just have to do the best you can with materials from the local home improvement store. Look at Sticking Doors and Loose Doors for ideas.
Replacing your cabinets is certainly possible if you can afford it. The standard cabinets sold in the home improvement stores will work, although they will probably be deeper than your existing cabinets.
I would suggest starting your cabinet shopping by looking through the cabinet selection at Ebay. The cabinets you see will all be designed for site built homes, but can probably be made to work in your mobile home. In any case you will be able to study what is available and learn about prices, materials and indicators of quality. Then, when you go shopping locally you will know what questions to ask and have a better idea of what the cost should be. Below is a list of kitchen cabinets currently available on Ebay