JMW uses Discovery wire, unless they changed. That's excellent wire, but if you want something more exotic I think Audio Origami is where you should go. They repair all brands of arms. They offer Cardas wire, but that's probably too stiff for that arm. You'll need Ikeda, Kondo, or SME, which they have. Maybe VdH or someone else offers that service? Origami has a good reputation. You should get in touch with them. He will know better than I, what's appropriate.
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