Looking at whether to use a Savage SA receiver for a .300 WSM (or an M700) , can't find one for sale?

NSS doesn't have one listed; and the WSM factory rifles don't specify action length on their website.

Does Savage even make a SA, magnum receiver- I don't mean just the boltface, I mean feed ramps for fat/wide magnums- or are all their magnums built on LA's?