A good auto parts store will have a 'grease injector' fitting--a hypodermiuc needle (big one!) with a grease zerk fitting on the end. It is used to lube 'sealed' bearings and other tight spots. Easy to punch a hloe in the joint boot (it reseals as soon as you pull the needle out) and pump in 4-6 shots of moly-sulfide grease. It helps lubrication to take the load off the joint by placing a jack under the control arm between the spring and ball joint.

Not a high probability of a permanent fix. The joints don't usually dry out and if they get scored they will wear rapidly.