Default Volume Rocker Replacement

Has anyone come across a replacement for the volume rocker? Somehow, the top and bottom portions of mine cracked, with the top coming off completely and falling out. Now I can't use the side button to increase volume... and the bottom is still cracked and barely hanging in there. Kinda annoying.

I came across threads with other HTC devices where the user called HTC and they shipped a replacement cover - anyone have an idea if that would work now that I have voided my warranty by unlocking the bootloader?

Anyway, I was hoping to not have to pay $40-$50 for an entirely new back cover (the rest of my phone is virtually flawless), but eventually will if I can't find any other solution. Thanks in advance for any help.