Thanks, but that does not sound like what I'm after.
With an OD of 20.5mm and an ID of 13.4mm it will be a 3.55mm wire, which will be extremely stiff.
The thing about the 13.8mm OEM spring is that it fits very well on the OEM HW95 spring guide, and I find it to be quicker and less "bouncy" than the 14.3mm ID spring with the same wire.