The newer Savage actions are center-feed, older (like mine) are staggered-feed.
My mag is attached to the receiver- yours would remain in the stock when you remove the receiver.
Just "ASSuming" here- but it looks like you need to replace the magazine, not just the follower (?) due to the fact that you have a center feed. Were it a staggered-feed, I think just the spring follower would need to be replaced.