pin. I lost mine somehow, so where do I go to get one? The lower is an Eagle Arms, so I guess I will try Armalite first, lol. Real question is how easy are these to replace once I get one? Any installation tips? Thanks in advance!

Most of the dealers in the industry section sell them, the only problem is you will pay more for shipping than the part cost.
Better to try local gun shops/smiths.
As for installation, the only thing to be wary of is pinching the spring when replacing the butt stock.

How did that happen? Did you have the stock off or something?

You should be able to find them about anywhere such as www.sogarmory.com/default.aspx

Click on the parts link on the left and they have the entire pin kit there to buy.

If it's the rear take down pin near the stock you will have to loosen your locknut on the stock and move the plate that is between the locknut and the lower. You will see a little hole there where your spring goes in. Put your pin back in the hole with the slot side facing the stock and then push the spring in the hole. You will have to hold it in there with one hand while you push that plate back against the lower to hold the spring in. Be careful not to pinch the spring. I have found using a samll precision type flathead screw driver works very well. Tighten the locknut back up and that should be it.

Someone else may have a better solution but I think that's it.

Tommy at [url]www.georgiaprecision.com[/url] can ship you out individual small parts if needed.  He has a cheap shipping rate for small parts.

Actually I just put a Cav Arms telestock on it. Well, had it put on by a gunsmith friend neway. Guess he will have to find the spring he lost. If not, is there a spring and a detent, or will I just have to replace the spring?

There is a spring and detent pin, take the stock off again and look in the hole.
The pin may still be in there.
Click here for the diagram:

[url]http://www.bushmaster.com/images/lower.gif[/url]

No offense to your friend, but I don't think I'd let him work on any of my guns again if I were you!