Are Model 70 WSSM in WSSM any different than a regular 70 S/A other than the bolt face? Any wildcats you could build on that action by rebarreling?

I don't have much experience with the M70, but I seem to remember that when they first came out with the WSSM in the M70 they had problems with the chamber stretching. I think the tenon is 1" so the chamber walls end up pretty thin. I think their solution was to use a finer pitch thread on the tenon? So depending on the version you have, the tenon might be different from a standard M70.

There are zillions of wildcats you could build.

Action is shorter than the short Model 70

The brass, that I used, was junk. Unless someone, other than Win., is making good brass, I'll pass.