Woodlecj: Welcome. If you are planning to come to my neck of the woods, let me know ahead of time and we can meet and say hello.
jpdown has said it correctly. Current Savage rifles with detachable box magazines are of two different types. which both utilize the same magazine box, same spring, and the same follower as the internal magazines. The difference is in the floorplate.

The magazines with the metal floorplate go into a stock with a metal DBM frame. The release lever is attached to the DBM frame, not to the magazine. This system is used in the accustock and some other models.

The magazines with the composite floorplate go into a stock with a matching composite DBM frame (or into a Savage Axis). In this case, the release lever is an integral part of the floorplate and is NOT attached to the DBM frame.

I believe all accustocks have the DBM, but I don't actually know that to be true. There may be some internal magazine or hinged floorplate accustocks...I just don't know.

And you are correct, with all the models and variations it is difficult to know exactly what is out there.