Viscous coupling

Hi all,
It might be time for me to look into an upgrade. I have not done any testing on mine yet, but the front wheels lag the rear more than they used to. In the past the front would stay almost in time with the rear in slippery conditions. On this trip, the rear wheels would spin well before the front would do any work, which is not ideal.

Anyone have a viscous coupling for sale, even if the it has gone “aggressive” as I have a decoupler. Otherwise I might get a solid shaft so I can send mine away for a rebuild.