Thanks for the replies - I will look at the other coils at Parts Express, but the unit spec'd in the Noise Nuke parts list is ~$21 at Parts...
Would this 6mH coil from Parts Express work? https://www.parts-express.com/Dayton-Audio-IC186-6.0mH-18-AWG-Laminated-Iron-Core-Inductor-257-672 Is...
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