It would be better to repair your old one. It shouln't cost much money unless it is really damaged. Also If you buy an all new one then you hsve to haul it to your RV, pull the other one out, install the new one, and make sure it works and well.
The old refrigerator can be repaired the new ones nowadays are not worthwhile and they work for a short duration compared to the materials in the older one. So it is sufficient when a reliable person is their and repairs it well then it is well and good.