You could try power steering no leak, stop leak, or conditioner. I have not used any of these products. Some of the products here are only fluid, not a conditioner.
If you are into DIY, or have an independent mechanic, you could get a rebuilt pump or one from an auto wrecker. Auto parts stores should carry generic replacement hoses and perhaps the cooler, but these also could be purchased at a wrecker.
For your own peace of mind, you should track down the leak.
I've used molybdenum disulfide lubricant as an additive to the PS fluid. It seems to have done the job as many of my cars have over 100K miles on them.
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