If you end up buying a new housing on eBay, expect lower quality.
I ordered a body, it came with everything except for the back of the LCD (the part that has the slider that connects both halves together). The battery cover was aluminum (but lighter, less reflective paint). The plastic was quite light, and on the keyboard, where the seam is for the silver sides and the center section, the join is visible, not as nice as the original. However, the fascia was aluminum (or some other metal) - probably the best quality thing of it all, although the camera and light sensor holes seemed frosted.
I never got to using this body, but I'll keep it as a spare in case something disastrous happens.
tl;dr: Expect lower quality from eBay, will do the trick, may have missing parts.