Buddy of mine at the base has a Colt .22 Conversion kit still in the box with (3) of the white magazines that go with it. He's asking $300. Is it worth that or what? Any help would be appreciated. Thanks in advance.

The only conversion unit I ever saw with white plastic mags (the shape and size of 30 round .223 mags, but only holding ten .22s) was the US Air Force conversion unit.  If that's what your buddy has, it's a $125 dollar value, or if it's brand new, maybe $150, since it's got 3 mags.

It's not a Colt made unit, which ain't neccessarily a bad thing.  It's also the only .22 conversion unit I'm aware of that holds the bolt open after the last round. The Army unit doesn't, which is why I sold off my Army unit a couple of years ago, and kept the Air Force unit.  

I think your friend ain't necessarily such a good friend, if he's trying to get that kind of money out of you for this item.  Also, since you mention that you're at a base,  if that's an Air Force base, you might want to check out where he got it.  Don't think you'd want get get hung on somebody elses "moonlight requisition".[:D]

The Colt kit's magazines are squared hunks of black (at least thats all I have ever seen) plastic, screwed together with the ejector mounted on the left feed lip (watch out, if you're not careful that thing will slice your thumb open very easily).  All used .22 conversions sell for about $100 with a single 10 round mag.  Extra mags are usually $~20-25.

Kharn