1. Please do not double post. If you need to go back and add something just click the modify button at the top right of your post.
2. The problem with your analog stick is most likely not the stick itself, but the motherboard. This happens when the motherboard gets old and is exposed to moisture for long periods of time. You can try serching for Joysens (a program that can help to fix a faulty analog stick) on google.
3. You can find the clip you are looking for on
www.dealextreme.com for really cheap. But i must warn you that de-soldering and then re-soldering the new clip is difficult to do and requires good soldering skills. Your best bet is to either get someone who can solder it for you to do it or to simply save yourself the money and add a small piece of paper on top of the clip to hold it down.
It sounds stupid i know but it works.
Hope it works out for you! And looking forward to seeing your work!