That's not a recumbent specific part so it should be relatively ely easy to find what you need.
1. If you can find a bike shop that's still open, try them. The older the shop the more likely they are likely to have what you need. If they like you it might even be a gimme part.
2. Look around for trash bikes. If you find one that has the cable anchor bolt that you need, grab it and throw everything else away.
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