Where can I find replacement parts for my Kyocera Rise?

I've only had this phone for a couple of months, and I'm already missing 3 connecting screws...at first they were just loose so I tightened them with a screwdriver, but then they started falling out when I took the back off, and they're so dang tiny that I lost them. Now my phone barely stays together...I've been to several Public Mobile stores and they said that they don't stock parts. I don't want to get a new phone because it has important data that I don't want to lose. Is there any way I can get replacement screws or at least ones that would fit my phone?