Ruger's never given production quantity info on their regular production guns. They're getting a lot better about that with their special distributor models though.
Unfortunately for any of the WSM or SUM calibers in a Ruger, ammunition availability is going to be the biggest detriment to the guns, and will probably have a drastic effect on collectibility.
Now as far as the .325 WSM of which only a handful were built in one model and maybe 100 in another model, I think those are going to be hot property (and already are!).
Chet15