How to reinstall google play store app in jellybean? I have telus samsung galaxy s2x with android jellybean 4.1.2 (non rooted).

When going on play store I got an error about authentication needed. So I did uninstall updates from application manager (as described in this answer). Now the play store app got replaced with com.android.vending, which is like the old "market" app.

That app seems to crash frequently. How can I restore the new play store app again?
Android Police has all the apks. Here's the lastest one.