How can I update the default stock browser (com.android.browser)? I have version 2.3.3 of the stock android browser on my phone.  I know there are newer versions out that support features that I want which are not available in 2.3.3.  However, I do not see any upgrades available, and in fact the stock browser does not even show up in the Google Play store.

I figure I probably need to manually install from somewhere, but where do I find the necessary files and how do I perform the upgrade?  Note: I am not interested in upgrading to a newer version of Android.
Check this XDA post. It has an APK for a 4.2 AOSP browser.

NOTE: Install at your own risk.