MOhunter, you might stop by the new members introduction section and introduce yourself to the membership when you get time. That said, there are only two sources that I am aware of at this point for Mini-14 gas port bushings, myself and Gundoc. They come in a set of three sizes so you can tune your rifle. You can contact Gundoc at www.greatwestgunsmithing.com
or myself via PM.
You will not need to replace your gas block screws if you take care in removing them.