i posted this in another thread, but think it applies here too...i tried these cleaning cloths that seem to work well to refresh strings and bring back new tone. Not sure what they'd do for rust, but could be worth a shot, they worked well on my dead strings...
Amazon.com: BassBrites Advanced String Cleaner and Protectant - Strings Last up to 5 Times Longer: Musical Instruments
Amazon.com: BassBrites Advanced String Cleaner and Protectant - Strings Last up to 5 Times Longer: Musical Instruments
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