Read the sticky at the top of the forum.
I *STRONGLY* recommend against buying a $30 kit from Wal Mart. It will last a few months, if it ever works.
You can buy the adapters for around $5 apiece, but it takes quite a bit more than that for it to actually work.
If you don't have evacuation and flushing equipment at home, you may not save much by doing the retrofit yourself. In fact, if you screw it up, you will lose quite a bit over what a shop costs. And do you have the expertise to condemn a compressor? Miss that, and whatever work you do (including new parts) will be wasted.
And you need a REPAIR. A retrofit might be reasonable as well, but the problem at hand is that something needs fixing. Even if it's "only" a leak. It is impossible to make a good installation that leaks. You WILL get water vapor in it.