Rovertrack (ex-US) and Ashcroft (ex-UK) are probably the aftermarket CV's to get. These come with axles already which are 24spline into the CV - not factory CV has this spline count into the CV.
All of the strong aftermarket CV's and axles will come back to the diff as 24 spline.
I don't know of any strong factory CV with the exception of having new ones heat treated, but the compromise there is that the heat treated ones will wear quickly in comparison.
