3D print/stock material similar to Hytrel 6356/ TPC-ET

Skills materials and processes
2

Taulman may have something that meets your specifications:

T-lyne comes at a 65D durometer: http://taulman3d.com/t-lyne-spec.html

There is also PCTPE: PCTPE Features

Or the proven Ninjaflex filament at about 30D / 85A hardness.