Check this out:
My ear speaker stopped working and sprint told me they could not replace it. Is there a way I could do it myself? Can it be done?
Yep I bought a used 8130 off ebay and the earspeaker volume was so low I could barely hear the person on the other end. I found a new speaker on ebay and replaced it. The phone is loud and clear again. It's very easy to do.
snnxp's link above is a great source for parts also, I've ordered quite a few items from them and have never been disappointed.
Thanks guys I'll check it out~via smartphone~