Need Some Advice Re. RV Refridgerator

I would think that you can pretty well evaluate by eye the rest of the fridge and determine if it's about to give up the ghost or not. If the interior plastics are not brittle and the insulation in good shape and the door works well and so forth, I would go for the cooling unit myself in your shoes. It takes a lot of nickels and dimes replacing other bits to make up the cost of a new fridge...and there's no guarantee that the new one is going to last a lot better.

Note: I haven't had to make this decision myself, so this is not based on actual personal experience.